Mammalian receptor proteins; related reagents and methods

ABSTRACT

Nucleic acids encoding mammalian, e.g., primate, receptors, purified receptor proteins and fragments thereof. Antibodies, both polyclonal and monoclonal, are also provided. Methods of using the compositions for both diagnostic and therapeutic utilities are described.

This filing is a Continuation of commonly assigned, co-pending U.S.patent application Ser. No. 10/720,026, filed Nov. 21, 2003, which is aContinuation-In-Part of commonly assigned, co-pending U.S. patentapplication Ser. No. 10/667,290, filed Sep. 18, 2003, which is aDivisional of U.S. patent application Ser. No. 09/853,180, filed May 10,2001, now U.S. Pat. No. 6,756,481, issued Jun. 29, 2004, which claimsbenefit of U.S. Provisional Patent Application No. 60/203,426, filed May10, 2000, each of which is incorporated herein by reference in itsentirety.

FIELD OF THE INVENTION

The present invention relates to compositions and methods for affectingmammalian physiology, including immune system function. In particular,it provides methods to regulate development and/or the immune system.Diagnostic and therapeutic uses of these materials are also disclosed.

BACKGROUND OF THE INVENTION

Recombinant DNA technology refers generally to techniques of integratinggenetic information from a donor source into vectors for subsequentprocessing, such as through introduction into a host, whereby thetransferred genetic information is copied and/or expressed in the newenvironment. Commonly, the genetic information exists in the form ofcomplementary DNA (cDNA) derived from messenger RNA (mRNA) coding for adesired protein product. The carrier is frequently a plasmid having thecapacity to incorporate cDNA for later replication in a host and, insome cases, actually to control expression of the cDNA and therebydirect synthesis of the encoded product in the host. See, e.g.,Sambrook, et al. (1989) Molecular Cloning: A Laboratory Manual, (2d ed.)vols. 1-3, CSH Press, NY.

For some time, it has been known that the mammalian immune response isbased on a series of complex cellular interactions, called the “immunenetwork”. Recent research has provided new insights into the innerworkings of this network. While it remains clear that much of the immuneresponse does, in fact, revolve around the network-like interactions oflymphocytes, macrophages, granulocytes, and other cells, immunologistsnow generally hold the opinion that soluble proteins, known aslymphokines, cytokines, or monokines, play critical roles in controllingthese cellular interactions. Thus, there is considerable interest in theisolation, characterization, and mechanisms of action of cell modulatoryfactors, an understanding of which will lead to significant advancementsin the diagnosis and therapy of numerous medical abnormalities, e.g.,immune system disorders.

Lymphokines apparently mediate cellular activities in a variety of ways.See, e.g., Paul (ed.) (1996) Fundamental Immunology 3d ed., Raven Press,New York; and Thomson (ed.) (1994) The Cytokine Handbook 2d ed.,Academic Press, San Diego. They have been shown to support theproliferation, growth, and/or differentiation of pluripotentialhematopoietic stem cells into vast numbers of progenitors comprisingdiverse cellular lineages which make up a complex immune system. Properand balanced interactions between the cellular components are necessaryfor a healthy immune response. The different cellular lineages oftenrespond in a different manner when lymphokines are administered inconjunction with other agents.

Cell lineages especially important to the immune response include twoclasses of lymphocytes: B cells, which can produce and secreteimmunoglobulins (proteins with the capability of recognizing and bindingto foreign matter to effect its removal), and T cells of various subsetsthat secrete lymphokines and induce or suppress the B cells and variousother cells (including other T cells) making up the immune network.These lymphocytes interact with many other cell types.

Research to better understand and treat various immune disorders hasbeen hampered by the general inability to maintain cells of the immunesystem in vitro. Immunologists have discovered that culturing many ofthese cells can be accomplished through the use of T cell and other cellsupernatants, which contain various growth factors, including many ofthe lymphokines.

Various growth and regulatory factors exist which modulate morphogeneticdevelopment. Many receptors for cytokines are known. Often, there are atleast two critical subunits in the functional receptor. See, e.g.,Heinrich, et al. (1998) Biochem. J. 334:297-314; Gonda and D'Andrea(1997) Blood 89:355-369; Presky, et al. (1996) Proc. Natl. Acad. Sci.USA 93:14002-14007; Drachman and Kaushansky (1995) Curr. Opin. Hematol.2:22-28; Theze (1994) Eur. Cytokine Netw. 5:353-368; and Lemmon andSchlessinger (1994) Trends Biochem. Sci. 19:459-463.

From the foregoing, it is evident that the discovery and development ofnew soluble proteins and their receptors, including ones similar tolymphokines, should contribute to new therapies for a wide range ofdegenerative or abnormal conditions which directly or indirectly involvedevelopment, differentiation, or function, e.g., of the immune systemand/or hematopoietic cells. In particular, the discovery andunderstanding of novel receptors for lymphokine-like molecules whichenhance or potentiate the beneficial activities of other lymphokineswould be highly advantageous. The present invention provides newreceptors for ligands exhibiting similarity to cytokine likecompositions and related compounds, and methods for their use.

SUMMARY OF THE INVENTION

The present invention is directed to novel receptors related to cytokinereceptors, e.g., primate, cytokine receptor-like molecular structures,designated DNAX Cytokine Receptor Subunits (DCRS), and their biologicalactivities. In particular, it provides description of one subunit,designated DCRS5 (a.k.a. IL-23R). It includes nucleic acids coding forthe polypeptides themselves and methods for their production and use.The nucleic acids of the invention are characterized, in part, by theirhomology to cloned complementary DNA (cDNA) sequences enclosed herein.Additionally, the invention provides matching of the p40/p19 ligand withreceptor subunits DCRS5 and IL-12Rβ1, which pairing provides insightinto indications for use of the agonists and antagonist based uponreagents directed thereto.

The present invention provides a substantially pure or recombinantpolypeptide comprising at least ten contiguous amino acids of theintracellular portion of SEQ ID NO:2. In certain embodiments, thepolypeptide: comprises at least 25 contiguous amino acids of theintracellular portion of SEQ ID NO:2; is recombinant, comprising theintracellular portion of SEQ ID NO:2; further comprises at least tencontiguous amino acids of the non-intracellular portion of SEQ ID NO:2;comprises at least 25 amino acids of the extracellular portion of SEQ IDNO:2; comprises the mature SEQ ID NO:2; or is a substantially purenatural polypeptide. In others, the recombinant polypeptide: consists ofthe mature sequence of SEQ ID NO:2; is an unglycosylated polypeptide; isfrom a human; comprises at least 40 contiguous amino acids of SEQ IDNO:2; exhibits at least three nonoverlapping segments of at leastfifteen contiguous amino acids of SEQ ID NO:2; is a natural polymorphicvariant of SEQ ID NO:2; has a length at least about 30 amino acids;exhibits at least two non-overlapping epitopes which are specific for aprimate DCRS5; has a molecular weight of at least 30 kD with naturalglycosylation; is a synthetic polypeptide; is in a sterile form; is inan aqueous or buffered solution; is attached to a solid substrate; isconjugated to another chemical moiety; or is physically associated withan IL-12Rβ1 polypeptide.

Other embodiments of the invention provide: a substantially pure orrecombinant polypeptide comprising at least twelve contiguous aminoacids of the intracellular portion of SEQ ID NO:2; or a substantiallypure natural sequence polypeptide comprising mature SEQ ID NO:2. Inparticular forms, the polypeptide comprising at least two distinctnonoverlapping segments of at least six contiguous amino acids of theintracellular portion of SEQ ID NO:2 will be where: the distinctnonoverlapping segments: include one of at least twelve amino acids;include one of at least seven amino acids and a second of at least nineamino acids; include a third distinct segment of at least six aminoacids; or comprise one of R355-L373, P378-L405, V407-D426, K428-D439,P441-V452, 1454-G460, 1465-T587, or N592-606; or the polypeptide furthercomprises at least two distinct nonoverlapping segments of at least sixcontiguous amino acids of the extracellular portion of SEQ ID NO:2.Alternatively, the polypeptide comprising at least twelve contiguousamino acids of the intracellular portion of SEQ ID NO:2 will be onewhere: the at least twelve contiguous amino acid segment comprises oneof R355-L373, P378-L405, V407-D426, K428-D439, P441-V452, I454-G460,I465-T587, or N592-606; or the polypeptide further comprises at leasttwo distinct nonoverlapping segments of at least six contiguous aminoacids of the extracellular portion of SEQ ID NO:2. Or, the pure naturalsequence polypeptide comprising mature SEQ ID NO:2 may furthercomprising a purification or detection epitope. Such polypeptides may:consist of the mature sequence of SEQ ID NO:2; be an unglycosylatedpolypeptide; be from a human; comprise at least 40 contiguous aminoacids of SEQ ID NO:2; exhibit at least three nonoverlapping segments ofat least fifteen contiguous amino acids of SEQ ID NO:2; be a naturalpolymorphic variant of SEQ ID NO:2; have a length at least about 30amino acids; exhibit at least two non-overlapping epitopes which arespecific for a primate DCRS5; have a molecular weight of at least 30 kDwith natural glycosylation; be a synthetic polypeptide; be in a sterileform; be in an aqueous or buffered solution; be attached to a solidsubstrate; be conjugated to another chemical moiety; or be physicallyassociated with an IL-12Rβ1 polypeptide.

Various other compositions are provided, e.g., comprising: asubstantially pure polypeptide combined with the IL-12Rβ1 protein; orsuch a polypeptide in a carrier, wherein the carrier is: an aqueouscompound, including water, saline, and/or buffer; and/or formulated fororal, rectal, nasal, topical, or parenteral administration.

Kits are provided comprising such a polypeptide and; a compartmentcomprising the polypeptide; a compartment comprising an IL-12R□1polypeptide; a compartment comprising a p40, p19, or p40/p19polypeptide; or instructions for use or disposal of reagents in the kit.

Antibodies and other binding compounds are provided, e.g., comprising anantigen binding site from an antibody, which specifically binds to theintracellular portion of the DCRS5, wherein: the binding compound is ina container; the polypeptide is from a human; the binding compound is anFv, Fab, or Fab2 fragment; the binding compound is conjugated to anotherchemical moiety; or the antibody: is raised against a peptide sequenceof a mature polypeptide of Table 1; is raised against a mature DCRS5; israised to a purified human DCRS5; is immunoselected; is a polyclonalantibody; binds to a denatured DCRS5; exhibits a Kd to antigen of atleast 30 μm; is attached to a solid substrate, including a bead orplastic membrane; is in a sterile composition; or is detectably labeled,including a radioactive or fluorescent label. Kits are also providedcomprising the binding compound and; a compartment comprising thebinding compound; a compartment comprising: a p40 polypeptide; a p19polypeptide; a DCRS5 polypeptide; and/or an IL-12Rβ1 polypeptide; acompartment comprising an antibody which binds selectively to: a p40polypeptide; a p19 polypeptide; a DCRS5 polypeptide; and/or an IL-12Rβ1polypeptide; or instructions for use or disposal of reagents in the kit.

Also provided are methods, e.g., of producing an antigen:antibodycomplex, comprising contacting under appropriate conditions a primateDCRS5 polypeptide with an antibody, thereby allowing the complex toform. Such method may be where: the complex is purified from othercytokine receptors; the complex is purified from other antibody; thecontacting is with a sample comprising an interferon; the contactingallows quantitative detection of the antigen; the contacting is with asample comprising the antibody; or the contacting allows quantitativedetection of the antibody. Other compositions are provided, e.g.,composition comprising: a sterile binding compound, or the bindingcompound and a carrier, wherein the carrier is: an aqueous compound,including water, saline, and/or buffer; and/or formulated for oral,rectal, nasal, topical, or parenteral administration.

The invention also provides an isolated or recombinant nucleic acidencoding the DCRS5 polypeptide, wherein the: DCRS5 is from a human; orthe nucleic acid: encodes an antigenic peptide sequence of SEQ ID NO:2;encodes a plurality of antigenic peptide sequences of SEQ ID NO:2;exhibits identity over at least thirteen nucleotides to a natural cDNAencoding the segment; is an expression vector; further comprises anorigin of replication; is from a natural source; comprises a detectablelabel; comprises synthetic nucleotide sequence; is less than 6 kb,preferably less than 3 kb; is from a primate; comprises a natural fulllength coding sequence; is a hybridization probe for a gene encoding theDCRS5; or is a PCR primer, PCR product, or mutagenesis primer. Cellscomprising the recombinant nucleic acid are provided, including wherethe cell is: a prokaryotic cell; a eukaryotic cell; a bacterial cell; ayeast cell; an insect cell; a mammalian cell; a mouse cell; a primatecell; or a human cell.

Kit embodiments include those comprising the nucleic acid and: acompartment comprising the nucleic acid; a compartment comprising anucleic acid encoding: a p40 polypeptide; a p19 polypeptide; a DCRS5polypeptide; and/or an IL-12Rβ1 polypeptide; a compartment comprising: ap40 polypeptide; a p19 polypeptide; a DCRS5 polypeptide; and/or anIL-112Rβ1 polypeptide; a compartment comprising an antibody whichselectively binds to: a p40 polypeptide; a p19 polypeptide; a DCRS5polypeptide; and/or an IL-12Rβ1 polypeptide; or instructions for use ordisposal of reagents in the kit.

Other nucleic acid embodiments include those which: hybridize under washconditions of 30 minutes at 30° C. and less than 2M salt to the portionof SEQ ID NO:1 encoding the intracellular portion; or exhibit identityover a stretch of at least about 30 nucleotides to the intracellularportion of a primate DCRS5. Preferably, such nucleic acid will be onewherein: the wash conditions are at 45° C. and/or 500 mM salt; or 55° C.and/or 150 mM salt; or the stretch is at least 55 or 75 nucleotides.

Therapeutic uses include methods of modulating physiology or developmentof a cell comprising contacting the cell with: an antagonist of p40/p19which is a complex comprising: the extracellular portion of a primateDCRS5 and/or the extracellular portion of a primate IL-12Rβ1; anantagonist of p40/p19 which is an antibody which binds a complexcomprising: primate DCRS5 and/or primate IL-12RP 1; an antagonist ofp40/p19 which is an antibody which binds to DCRS5; an antagonist ofp40/p19 which is an antibody to IL-12RP 1; an antagonist of p40/p19which is an antisense nucleic acid to DCRS5 or IL-12RP 1; or an agonistof p40/p19 which is an antibody which binds a complex comprising primateDCRS5 and/or primate IL-12RP 1. In one type of method, the contacting iswith an antagonist, and the contacting is in combination with anantagonist to IL-12, IL-18, TNF, and/or IFNγ; or the cell is from a hostwhich: exhibits signs or symptoms of a chronic TH1 mediated disease;exhibits symptoms or signs of multiple sclerosis, rheumatoid arthritis,osteoarthritis, inflammatory bowel disease, diabetes, psoriasis, orsepsis; or receives an allogeneic transplant. Conversely, the method maybe contacting with an agonist, and: the contacting is in combinationwith IL-12, IL-18, TNF, or IFNγ; or the cell is from a host which:exhibits signs or symptoms of a chronic TH2 response; suffers from atumor, viral, or fungal growth; receives a vaccine; or suffers from anallergic response.

The invention provides a method of treating a human subject experiencinga physiological disorder comprising administering an effective amount ofan agonist or antagonist of DCRS5 (SEQ ID NOs: 1 or 2) or of p19 (SEQ IDNOs:5 or 6), wherein the disorder comprises rheumatoid arthritis; asthmaor allergy; chronic obstructive pulmonary disorder (COPD); aninterstitial lung disorder; an inflammatory bowel disorder (IBD); or aninflammatory skin disorder. Also provided is the above method whereinthe skin disorder is psoriasis or atopic dermatitis; wherein the IBD isCrohn's disease or ulcerative colitis; wherein the interstitial lungdisorder is idiopathic pulmonary fibrosis; eosinophilic granuloma; orhypersensitivity pneumonitis.

In another embodiment, the invention provides the above method whereinthe antagonist comprises a binding composition derived from the antigenbinding site of an antibody that specifically binds to DCRS5 (SEQ IDNO:2); or p19 (SEQ ID NO:6); or the above method wherein the bindingcomposition comprises a polyclonal antibody; a monoclonal antibody; ahumanized antibody; or an Fab, Fv, or F(ab′)₂ fragment; or the abovemethod wherein the agonist comprises DCRS5 (SEQ ID NO:2) or p19 (SEQ IDNO:6), as well as the above method wherein the agonist or antagonistcomprises a nucleic acid, or wherein the antagonist comprises anantisense nucleic acid or an RNA interference nucleic acid.

Yet another embodiment of the present invention is a method ofdiagnosing a physiological disorder comprising contacting a bindingcomposition that specifically binds to DCRS5 (SEQ ID NOs:1 or 2), or top19 (SEQ ID NOs:5 or 6), to a sample derived from a test subjectexperiencing rheumatoid arthritis; asthma or allergy; chronicobstructive pulmonary disorder (COPD); an interstitial lung disorder;inflammatory bowel disorder (IBD); or an inflammatory skin disorder.Also provided is the above method, further comprising contacting thebinding composition to a sample derived from a control subject orcontrol sample; and comparing the binding found with the test subjectwith the binding found with the control subject or control sample.Provided is the above method, wherein the binding composition comprisesa polyclonal antibody; a monoclonal antibody; a humanized antibody; anFab, Fv, or F(ab′)₂ fragment; a nucleic acid; or a detectable label; aswell as the above method wherein the nucleic acid comprises a probe orprimer; or a molecular beacon.

In another embodiment, the invention provides the above method ofdiagnosis wherein the sample is derived from a human cell, tissue, orbiological fluid; wherein the skin disorder is psoriasis or atopicdermatitis; wherein the IBD is Crohn's disease or ulcerative colitis; orwherein the interstitial lung disorder is idiopathic pulmonary fibrosis;eosinophilic granuloma; or hypersensitivity pneumonitis.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As used herein, including the appended claims, the singular forms ofwords such as “a,” “an,” and “the,” include their corresponding pluralreferences unless the context clearly dictates otherwise. All referencescited herein are incorporated by reference to the same extent as if eachindividual publication, patent application, or patent, was specificallyand individually indicated to be incorporated by reference.

I. General

The present invention provides the amino acid sequence and DNA sequenceof mammalian, herein primate, cytokine receptor-like subunit molecules,this one designated DNAX Cytokine Receptor Subunit 5 (DCRS5) havingparticular defined properties, both structural and biological. VariouscDNAs encoding these molecules were obtained from primate, e.g., human,cDNA sequence libraries. Other primate or other mammalian counterpartswould also be desired.

Additionally, the invention provides matching of the p40/p19 ligand withreceptor subunits DCRS5 and IL-12Rb1, which pairing provides insightinto indications for use of the agonists and antagonists based uponreagents directed thereto.

Some of the standard methods applicable are described or referenced,see, e.g., Maniatis, et al. (1982) Laboratory Manual, Cold Spring HarborLaboratory, Cold Spring Harbor Press; Sambrook, et al. (1989) MolecularCloning: A Laboratory Manual, (2d ed.), vols. 1 3, CSH Press, NY;Ausubel, et al. (1987 and periodic supplements) Current Protocols inMolecular Biology, Greene/Wiley, New York.

Nucleotide (SEQ ID NO:1) and corresponding amino acid sequence (SEQ IDNO:2) of a primate, e.g., human, DCRS5 coding segment is provided. Thepredicted signal sequence is indicated, but may depend on cell type, ormay be a few residues in either direction. Potential N glycosylationsites are at Asparagine residues 6, 24, 58, 118, 157, 209, and 250 (SEQID NO:2). Disulfide linkages are likely to be found between cysteineresidues at positions 29 and 78; and a conserved C_CXW motif is found atpositions 110/121/123. The tryptophan at 219; and the WxxWS motif from281-285 are notable. The segment from about 1-101 is an Ig domain; fromabout 102-195 is a cytokine binding domain 1; from about 196-297 is acytokine binding domain 2; from about 298-330 is a linker; from about329-354 is a transmembrane segment; and from about 356-606 is anintracellular domain. Intracellular features include putative SH2binding sites at Y374-I377, Y461-Q464, and Y588-Q591; and potentiallyimportant tyrosine residues at 406, 427, 440, and 453.

The open reading frame (ORF) contains a putative signal sequence whichis predicted to be cleaved at . . . CHG/GIT . . . as shown above. Apredicted extracellular domain of 328 amino acids is followed by aputative transmembrane segment, and finally a cytoplasmic domain ofabout 252 amino acids. The ligand-binding functions are predicted toreside in the extracellular domain. Identified positions of variationare at nucleotides 127 and 563 (SEQ ID NO:1). The codon containingnucleotide 127 could encode histidine or glutamine, while the codoncontaining nucleotide 563 could encode arginine, glycine, or tryptophan.

TABLE 1 Alignment of various cytokine receptor subunits. Human IL-6receptor protein gp130 is SEQ ID NO:3 (GenBank M57230); human IL-12receptor beta2 subunit is SEQ ID NO:4 (GenBank U64198). huIL-12Rβ2 1MAHTFRGCSLAFMFIITWLLIKAKIDACKRGDVTVKPSHVILLGSTVN 48 hugp130 1MLTLQTWVVQALFIFLTTESTGELLDPCG---YISPESPVVQLHSNFT 45 huDCRS5 1MNHVTTQWDAVIALYILFSWCHGGITNINCS-GHIWVEPATIFKMGMNIS 49            *     .          *         . .  .  . huIL-12Rβ2 49ITCSLKPRQGCFHYSRRNKLILYKFDRRINFHHGHSLNSQVTGLPLG--- 95 hugp130 46AVCVLKEKCMDYFHVNANYIVWKTNHFTIPKEQYTIINRTASSVTFTDIA 95 huDCRS5 50IYCQAAIKN--CQP---RKLHFYKNGIKER-FQITRINKTTARLWYKNFL 93  *    .           .            .   .*   . . huIL-12Rβ2 96--TTLFVCKLACINSD-EIQICGAEIFVGVAPEQPQNLSCIQKGEQGTVA 142 hugp130 96SLNIQLTCNILTFGQL-EQNVYGITIISGLPPEKPKNLSCIVN-EGKKMR 143 huDCRS5 94EPHASMYCTAECPKHFQETLICGKDISSGYPPDIPDEVTCVIYEYSGNMT 143       *   .     *  . *  *  *  *. *  ..*.       . huIL-12Rβ2 143CTWERGRDTHLYTEYTLQLSGPKNLTWQKQCKDIYCDYLDFGINLTPESP 192 hugp130 144CEWDGGRETHLETNFTLKS--EWATHKFADCKAKRDTPTSCTVDYS-TVY 190 huDCRS5 144CTWNARKLTYIDTKYVVHVKSLETEEEQQYLTSSYINISTDSLQGG---- 189* *   . * . * . ..                        . huIL-12Rβ2 193ESNFTAKVTAVNSLGSSSSLPSTFTFLDIVRPLPPWDIRIKFQKASVSRC 242 hugp130 191FVNIEVWVEAENALGKVTSDHINFDPVYKVKPNPPHNLSVINSEELSSIL 240 huDCRS5 190-KKYLVWVQAANALGMEESKQLQIHLDDIVIPSAAVISRAETINATVPKT 238       * * *.**   *          * * huIL-12Rβ2 243TLYWRD----EGLVLLNRLRYRPSNSRLWNMVN---VTKAKGRHDLLDLK 285 hugp130 241KLTWTNPSIKSVIILKYNIQYRTKDASTWSQIPPEDTASTRSSFTVQDLK 290 huDCRS5 239IIYWDS--QTTIEKVSCEMRYKATTNQTWNVKEFD-TNFTYVQQSEFYLE 285 . *          .   ..*.      *          .        * huIL-12Rβ2 286PFTEYEFQISSKLHLYKGSWSDWSESLRAQTPEEEPTGMLDVWYMKRHID 335 hugp130 291PFTEYVFRIRCMKEDGKGYWSDWSEEASGITYEDRPSKAPSFWYKIDPSH 340 huDCRS5 286PNIKYVFQVRCQ-ETGKRYWQPWSSPFFHKTPETVP-------------- 320*   * *.. .     *  *  **      * *  * huIL-12Rβ2 336YS-RQQISLFWKNLSVSEARGKILHYQVTLQELTGGKAMTQNITGHTSWT 384 hugp130 341TQGYRTVQLVWKTLPPFEANGKILDYEVT---LTRWKSHLQNYTVNATKL 387 huDCRS5 321-----QVTSKAFQHDTWNSGLTVASISTG------HLTSDN--RGDIGLL 357      .           .   .              .  . huTL-12Rβ2 385TVIPRTGNWAVAVSAANSKGSSLPTRINIMNLCEAGLLAPRQVSANSEGM 434 hugp130 388TVNLTNDRYLATLTVRNLVGKSDAAVLTIP-ACDFQATHPVMDLKAFPKD 436 huDCRS5 358LGMIVFAVMLSILSLIGIFNRSFRTGIKRR-------------------- 387            ..  .  . *  . . huIL-12Rβ2 435DNILVTWQPPRKDPSAVQEYVVEWRELHPG-GDTQVPLNWLRSRPYNVSA 483 hugp130 437NMLWVEWTTPRE---SVKKYILEWCVLS---DKAPCITDWQQEDGTVHRT 480 huDCRS5 388----------------ILLLIPKWLYEDIPNMKNSNVVKMLQEN----SE 417                .   .  *                  huIL-12Rβ2 484LISENIKSYICYEIRVYALSGDQ-GGCSSILGNSKHKAPLSGPHINAITE 532 hugp130 481YLRGNLAESKCYLITVTPVYADGPGSPESIKAYLKQAPPSKGPTVRTKKV 530 huDCRS5 418LMNNNSSE--------QVLYVDP-----MITEIKEIFIPEHKPTDYKKE- 453 .  *             .  *       *        *   * huIL-12Rβ2 533EKGSILISWNSIPVQEQMGCLLHYRIYWKERDSNSQPQLCEIPYRVSQNS 582 hugp130 531GKNEAVLEWDQLPVDVQNGFIRNYTIFYRTIIGN----ETAVNVDSSHTE 576 huDCRS5 454--NTGPLETRDYP---QNSLFDNTTVVYIPDLNTG------YKPQISN-- 490  .   .     *   *     .  .       .            * huIL-12Rβ2 583HPINSLQPRVTYVLWMTALTAAGESSHGNEREFCLQGKAN-WMAFVAPSI 631 hugp130 577YTLSSLTSDTLYMVRMAAYTDEG-GKDGPEFTFTTPKFAQGEIEAIVVPV 625 huDCRS5 491------------------FLPEG--------------------------- 495                      * huIL-12Rβ2 632CIAIIMVGIFSTHYFQQKVFVLLAALRP-----------QWCSREIPDPA 670 hugp130 626CLAFLLTTLLGVLFCFNKRDLIKKHIWPNVPDPSKSHIAQWSPHTPPRHN 675 huDCRS5 496___________SHLSNNN-EITSLTLKP--------------PVDSLDSG 519                .   .    . * huIL-12Rβ2 671NSTCAKKYPIAEEKTQLPLDRLLID-WPTPEDPEPLVIS--EVLHQVTPV 717 hugp130 676FNSKDQMYSDGNFTDVSVVEIEANDKKPFPEDLKSLDLFKKEKINTEGHS 725 huDCRS5 520NNPRLQKHPN-FAFSVSSVNSLSNT-------------I---FLGELSLI 552     .            .                        . huIL-12Rβ2 718FRHPPCSNWPQREKGIQGHQASEKDMMHSASSPPPPRALQAESRQLVDLY 767 hugp130 726SGIGGSSCMSSSRPSISSSDENESSQNTSSTVQYSTVVHSGYRHQVPSVQ 775 huDCRS5 553LNQGECS---S--PDIQNSVEEETTMLLENDSP----------------- 580     .*        *      * huIL-12Rβ2 768KVLESRGSDPKPENPACPWTVLPAGDLPTHDGYLPSN---IDDLPSHEAP 814 hugp130 776VFSRSESTQPLLDSEERPEDLQLVDHVDGGDGTLPRQQYFKQNCSQHESS 825 huDCRS5 581--SETIPEQTLLPDEFVSCLGIVNEELPSINTYFPQN---ILESHFNR-- 623    .                     .       * .         . huIL-12Rβ2 815LADSLEELEPQHISLS-----VFPSSSLHPLTFSCG-------------- 845 hugp130 826PDISHFERSKQVSSVNEEDFVRLKQQISDHISQSCGSGQMKMFQEVSAAD 875 huDCRS5 624--ISLLEK 629    *  * huIL-12Rβ2 846 ----------DKLTLDQLKMRCDSLML 862hugp130 876 AFGPGTEGQVERFETVGMEAATDEGMPKSYLPQTVRQGGYMPQ 918 huDCRS5 630629

The closest relatives of the extracellular domain of “IL-30R” are theIL-6 signal transducer gp130 and IL-12Rβ2. Somewhat less close relativesare GCSF receptor, leptin receptor, leukemia inhibitory factor receptor,and CNTF receptor. Thus “IL-30R” is a member of the class I branch ofthe cytokine receptor superfamily and is closely related to theIL-6R/IL-12R family.

Table 1 shows comparison of the available sequences of primate receptorsubunits with the primate, e.g., human DCRS5 (IL-30R). The DCRS5 showssimilarity to the IL-6 receptor subunit gp130 (e.g., IL-6R subunit) andthe IL-12RP2 subunit. The DCRS5 exhibits structural features of a betasubunit, but the actual sequence of protein interactions and signalingremains unresolved.

As used herein, the term DCRS5 shall be used to describe a proteincomprising the amino acid sequence of SEQ ID NO:2. In many cases, asubstantial fragment thereof will be functionally or structurallyequivalent, including, e.g., additional extracellular segments. Theinvention also includes a protein variation of the respective DCRS5allele whose sequence is provided, e.g., a mutein or other construct.Typically, such variants will exhibit less than about 10% sequencedifferences with the target region, and thus will often have between 1-and 11-fold substitutions, e.g., 2-, 3-, 5, 7-fold, and others. It alsoencompasses allelic and other variants, e.g., natural polymorphisms, ofthe protein described. Typically, it will bind to its correspondingbiological ligand, perhaps in a dimerized state with an alpha receptorsubunit, with high affinity, e.g., at least about 100 nM, usually betterthan about 30 nM, preferably better than about 10 nM, and morepreferably at better than about 3 nM. The term shall also be used hereinto refer to related naturally occurring forms, e.g., alleles,polymorphic variants, and metabolic variants of the mammalian protein.Preferred forms of the receptor complexes will bind the appropriateligand with an affinity and selectivity appropriate for aligand-receptor interaction.

This invention also encompasses combinations of proteins or peptideshaving substantial amino acid sequence identity with the amino acidsequence of SEQ ID NOs:2 and 6. It will include sequence variants withrelatively few substitutions, e.g., preferably fewer than about 3-5.

Binding compositions specific for human p19 can be prepared byimmunization with an antigenic segment or fragment of p19. These bindingcompositions encompass polyclonal antibodies, monoclonal antibodies,humanized antibodies, antibody fragments, e.g., an Fab, Fv, or F(ab′)₂fragment, diabodies, single chain antibodies, bifunctional antibodies,and peptide mimetics of an antibody. Regions of increased antigenicityof human p19 include, e.g., amino acids 16-21; 57-69; 72-81; 136-140;143-146; 151-154; and 135-164, of SEQ ID NO:6, according to analysis byParker, et al. (1986) Biochemistry 25:5425-5432 and Welling, et al.(1985) FEBS Lett. 188:215-218, optionally with use of software fromVector NTI® Suite (Informax, Inc., Bethesda, Md.).

A substantial polypeptide “fragment”, or “segment”, is a stretch ofamino acid residues of at least about 8 amino acids, generally at least10 amino acids, more generally at least 12 amino acids, often at least14 amino acids, more often at least 16 amino acids, typically at least18 amino acids, more typically at least 20 amino acids, usually at least22 amino acids, more usually at least 24 amino acids, preferably atleast 26 amino acids, more preferably at least 28 amino acids, and, inparticularly preferred embodiments, at least about 30 or more aminoacids. Sequences of segments of different proteins can be compared toone another over appropriate length stretches. In many situations,fragments may exhibit functional properties of the intact subunits,e.g., the extracellular domain of the transmembrane receptor may retainthe ligand binding features, and may be used to prepare a solublereceptor-like complex.

Amino acid sequence homology, or sequence identity, is determined byoptimizing residue matches. In some comparisons, gaps may be introduces,as required, see, e.g., Needleham, et al., (1970) J. Mol. Biol.48:443-453; Sankoff, et al., (1983) chapter one in Time Warps, StringEdits, and Macromolecules: The Theory and Practice of SequenceComparison, Addison-Wesley, Reading, Mass.; software packages fromIntelliGenetics, Mountain View, Calif.; and the University of WisconsinGenetics Computer Group (GCG), Madison, Wis. This changes whenconsidering conservative substitutions as matches. Conservativesubstitutions typically include substitutions within the followinggroups: glycine, alanine; valine, isoleucine, leucine; aspartic acid,glutamic acid; asparagine, glutamine; serine, threonine; lysine,arginine; and phenylalanine, tyrosine. Homologous amino acid sequencesare intended to include natural allelic and interspecies variations inthe cytokine sequence. Typical homologous proteins or peptides will havefrom 50-100% homology (if gaps can be introduced), to 60-100% homology(if conservative substitutions are included) with an amino acid sequencesegment of SEQ ID NO:2. Homology measures will be at least about 70%,generally at least 76%, more generally at least 81%, often at least 85%,more often at least 88%, typically at least 90%, more typically at least92%, usually at least 94%, more usually at least 95%, preferably atleast 96%, and more preferably at least 97%, and in particularlypreferred embodiments, at least 98% or more. The degree of homology willvary with the length of the compared segments. Homologous proteins orpeptides, such as the allelic variants, will share most biologicalactivities with SEQ ID NO:2, particularly the intracellular portion.

As used herein, the term “biological activity” is used to describe,without limitation, effects on signaling, inflammatory responses, innateimmunity, and/or morphogenic development by cytokine-like ligands. Forexample, these receptors should mediate phosphatase or phosphorylaseactivities, which activities are easily measured by standard procedures.See, e.g., Hardie, et al. (eds.) (1995) The Protein Kinase FactBookvols. I and II, Academic Press, San Diego, Calif.; Hanks, et al. (1991)Meth. Enzymol. 200:38-62; Hunter, et al. (1992) Cell 70:375-388; Lewin(1990) Cell 61:743-752; Pines, et al. (1991) Cold Spring Harbor Symp.Quant. Biol. 56:449-463; and Parker, et al. (1993) Nature 363:736-738.The receptors, or portions thereof, may be useful as phosphate labelingenzymes to label general or specific substrates. The subunits may alsobe functional immunogens to elicit recognizing antibodies, or antigenscapable of binding antibodies.

The terms ligand, agonist, antagonist, and analog of, e.g., a DCRS5protein features of ligand-receptor interactions, e.g., where thereceptor is a natural receptor or an antibody. The cellular responseslikely are typically mediated through receptor tyrosine kinase pathways.

Also, a ligand is a molecule which serves either as a natural ligand towhich said receptor, or an analog thereof, binds, or a molecule which isa functional analog of the natural ligand. The functional analog may bea ligand with structural modifications, or may be a wholly unrelatedmolecule which has a molecular shape which interacts with theappropriate ligand binding determinants. The ligands may serve asagonists or antagonists, see, e.g., Goodman, et al. (eds.) (1990)Goodman & Gilman's: The Pharmacological Bases of Therapeutics, PergamonPress, New York.

Rational drug design may also be based upon structural studies of themolecular shapes of a receptor or antibody and other effectors orligands. See, e.g., Herz, et al. (1997) J. Recept. Signal Transduct.Res. 17:671-776; and Chaiken, et al. (1996) Trends Biotechnol.14:369-375. Effectors may be other proteins which mediate otherfunctions in response to ligand binding, or other proteins whichnormally interact with the receptor. One means for determining whichsites interact with specific other proteins is a physical structuredetermination, e.g., x-ray crystallography or 2 dimensional NMRtechniques. These will provide guidance as to which amino acid residuesform molecular contact regions. For a detailed description of proteinstructural determination, see, e.g., Blundell and Johnson (1976) ProteinCrystallography, Academic Press, New York.

II. Activities

The cytokine receptor-like proteins will have a number of differentbiological activities, e.g., intracellular signaling, e.g., via STAT4,modulating cell proliferation, or in phosphate metabolism, being addedto or removed from specific substrates, typically proteins. Such willgenerally result in modulation of an inflammatory function, other innateimmunity response, or a morphological effect. The subunit will probablyhave a specific low affinity binding to the ligand.

The DCRS5 has the characteristic motifs of a receptor signaling throughthe JAK pathway. See, e.g., Ihle, et al. (1997) Stem Cells 15 (suppl.1):105-111; Silvennoinen, et al. (1997) APMIS 105:497-509; Levy (1997)Cytokine Growth Factor Review 8:81-90; Winston and Hunter (1996) CurrentBiol. 6:668-671; Barrett (1996) Baillieres Clin. Gastroenterol. 10:1-15;and Briscoe, et al. (1996) Philos. Trans. R. Soc. Lond. B. Biol. Sci.351:167-171. Of particular interest are the SH2 binding motifs describedabove.

The biological activities of the cytokine receptor subunits will berelated to addition or removal of phosphate moieties to substrates,typically in a specific manner, but occasionally in a non specificmanner. Substrates may be identified, or conditions for enzymaticactivity may be assayed by standard methods, e.g., as described inHardie, et al. (eds.) (1995) The Protein Kinase FactBook vols. I and II,Academic Press, San Diego, Calif.; Hanks, et al. (1991) Meth. Enzymol.200:38-62; Hunter, et al. (1992) Cell 70:375-388; Lewin (1990) Cell61:743-752; Pines, et al. (1991) Cold Spring Harbor Symp. Quant. Biol.56:449-463; and Parker, et al. (1993) Nature 363:736-738.

The receptor subunits may combine to form functional complexes, e.g.,which may be useful for binding ligand or preparing antibodies. Thesewill have substantial diagnostic uses, including detection orquantitation. The functional linkage of the receptor with the p40/p19ligand provides important insights into the clinical indications thatthe receptor will be useful for. Thus, antagonists and agonists willhave predicted functional effects.

With activation, mast cells, T cells, and NK cells show increasedexpression of the p19 subunit of IL-23, while activated dendritic cellsshow increased expression of the p40 subunit of IL-23. These cells havebeen implicated in the pathologies of various inflammatory disorders andconditions.

Mast cells play a role in the etiology of asthma and allergy, COPD,rheumatoid arthritis, IBD, e.g., Crohn's disease or ulcerative colitis,and skin inflammation, e.g., psoriasis and atopic dermatitis, see, e.g.,Edwards (2003) Clin. Exp. Allergy 33:1164-1165; Grashoff, et al. (1997)Am. J. Pathol. 151:1785-1790; Woolley (2003) New Engl. J. Med.348:1709-1711; Malaviya, et al. (1995) Am. J. Ther. 2:787-792; Jiang, etal. (2001) Int. J. Dermatol. 40:699-703.

NK cells are involved in the mechanisms of asthma and allergy,rheumatoid arthritis, and skin disorders, e.g., psoriasis or atopicdermatitis, see, e.g., Korsgren (2002) Curr. Pharm. Des. 8:1871-1876;Cameron, et al. (2003) Br. J. Dermatol 149:160-164.

DCs have been implicated in asthma and allergies, rheumatoid arthritis,inflammatory bowel disorders (IBDs) such as Crohn's disease orulcerative colitis, and skin disorders, e.g., psoriasis and atopicdermatitis, see, e.g., Upham (2003) Respirology 8:140-148;Santiago-Schwarz, et al. (2001) J. Immunol. 167:1758-1768; Stagg, et al.(2003) Gut 52:1522-1529; Mrowietz, et al. (2001) Exp. Dermatol.10:238-245.

The p19 subunit of IL-23 shows increased expression with various lungdisorders, e.g., interstitial lung disorders. The invention provides anagonist or antagonist of IL-23, e.g., a binding composition specific fora polypeptide or nucleic acid of p19 or DCRS5, for the treatment ordiagnosis of an interstitial lung disorder. Interstitial lung disordersinclude idiopathic pulmonary fibrosis, pulmonary eosinophilic granuloma,and hypersensitivity pneumonitis. Idiopathic pulmonary fibrosis, whichhas a grim prognosis, involves activated alveolar epithelial cells,fibroblastic foci, and deposit of extracellular matrix. Inflammationoccurs, but the major feature is fibroblastic foci (see, e.g., Kamp(2003) Chest 124:1187-1189; White, et al. (2003) J. Pathol.201:343-354). Pulmonary eosinophilic granuloma is a localizednonmalignant histiocytosis. It can resolve, or progress to a fibroticstage. The disorder is associated with smoking (see, e.g., Levine andNickelleit (1994) New Engl. J. Med. 330:347-353; Rajagopol and Mark(2002) New Engl. J. Med. 347:1262-1268; Miadonna, et al (2000) MonaldiArch Chest Dis. 55:3-5). Hypersensitivity pneumonitis (a.k.a. extrinsicallergic alveolitis), caused by inhaled allergens, involves inflammationin peripheral airways and surrounding interstitial tissues. Monocytesaccumulate and mature into foamy macrophages that develop intogranulomas. The disorder also involves bronchiolitis, interstitiallymphocyte infiltration, and may include a “honeycombed lung” fibrosis(see, e.g., Patel, et al. (2001) J. Allergy Clin. Immunol. 108:661-670;Yi (2002) Crit. Rev. Clin. Lab. Sci. 39:581-629).

The p19 subunit of IL-23 also shows increased expression withAscaris-treatment. Ascaris-treatment is a model for allergies andasthma. Helminth-treatment, e.g., Ascaris, is used in animal models ofpulmonary disorders, e.g., airway hyperreactivity; asthma, pulmonaryeosinophilia, and allergies. Ascaris-treatment induces pulmonaryeosinophilia, a characteristic feature of asthma. Ascaris also inducespulmonary neutrophilia, a characteristic feature of COPD. Exposure toAscaris has been associated asthma in humans (see, e.g., Billah, et al.(2002) J. Pharmacol. Exp. Therapeutics 302:127-137; Mochizuki, et al.(2001) Eur. J. Pharmacol. 430:123-133; Boucher, et al. (1979) J. AllergyClin. Immunol. 64:197-201; Padrid, et al. (1995) Am. J. Respir. Crit.Care Med. 151:184-193; Sengoku, et al. (2001) Pharmacol. 63:82-89;Abraham, et al. (1999) Am. J. Respir. Crit. Care Med. 159:1205-1214;Jones, et al. (1998) Can. J. Physiol. Pharmacol. 76:210-217; Wright, etal. (1999) J. Pharmacol. Exp. Therapeutics 289:1007-1014; D'Brot, et al.(1989) Am. Rev. Respir. Dis. 139:915-920; Barnes (2000) New Engl. J.Med. 343:269-280; Palmer, et al. (2002) Am. J. Respir. Crit. Care Med.165:1489-1493; Lynch, et al. (1997) Am. J. Respir. Crit. Care Med.156:50-54).

Increased expression of the p19 subunit of IL-23 and of IL-23R occurs inIBD, e.g., Crohn's disease. Moreover, helminths, protozoans, andparasites have been associated with an increased incidence in intestinalinflammation, e.g., IBD (see, e.g., Sacco, et al. (1998) Am. J. Pathol.153:1717-1722; Takeyama, et al. (1997) J. Gastroenterol. Hepatol.12:204-206; Bundy (1986) Trans. R. Soc. Trop. Med. Hyg. 80:706-718;Tanaka, et al. (1983) Parasitology 86:291-300; Ustun, et al. (2003)World J. Gastroenterol. 9:1834-1835; Waters, et al. (1999) J. Parasitol.85:1100-1105; Faussone-Pellegrini, et al. (2002) Neurogastroenterol.Motil. 14:83-95).

The IL-23R of the present invention increases in expression on Claracells of patients with COPD. Clara cells are nonciliated respiratoryepithelial cells of the airways that modulate airway pathology in, e.g.,asthma, cigarette smoking, and COPD. COPD has been correlated withchanges in Clara cell physiology (see, e.g., Pilette, et al. (2001) Am.J. Respir. Crit. Care Med. 163:185-194; Kaup, et al. (1990) Equine VetJ. 22:349-355; Zhang, et al. (2001) Zhonghua Jie He He Hu Xi Za Zhi24:524-526). Clara cells produce a number of molecules that modulateimmune response, e.g., uteroglobulin (a.k.a. Clara cell secretoryprotein). In asthma and COPD, there is a decrease in Clara cells and anincrease in mucous cells, where the consequent increase in mucusproduction contributes to airway obstruction. Clara cells appear to beprecursor cells to mucous cells (see, e.g., Jeffrey (1998) Thorax553:129-136; Rogers (2002) Clin. Exp. Allergy 32:1124-1127; Watson, etal. (2001) Am. J. Physiol. Lung Cell Mol. Physiol. 281:L1523-L1530;Reader, et al. (2003) Am. J. Physiol. 162:2069-2078; Stripp, et al.(2002) Am. J. Respir. Cell Mol. Biol. 27:170-178). Fibrosis is a featureof the pathology of asthma and chronic obstructive pulmonary disorder(COPD), see, e.g., Barnes (2000) New Engl. J. Med. 343:269-280; Barnes(2000) Chest 117: 10s-14s; Saetta, et al. (2001) Eur. Respir. J. Suppl.34:18s-23s; Redington (2000) Monaldi Arch. Chest Dis. 55:317-323;Vignola, et al. (2001) Curr. Allergy Asthma Rep. 1: 108-115.

Cytokines, such tumor necrosis factor (TNF), IL-4, or IL-13, canstimulate expression of IL-23, p19, or DCRS5 (a.k.a. IL-23R).Conversely, IL-23 can stimulate expression of a number of cytokines,e.g., IL-6, IL-19, CXCL-1, and IL-17. TNF contributes to a number ofinflammatory disorders, such as asthma, COPD, rheumatoid arthritis,inflammatory bowel disorder (IBD), and psoriasis, see, e.g., Das, et al.(2002) Pulm. Pharmacol. Ther. 15:409-416; Halasz, et al. (2002) Respir.Med. 96:262-267; Barnes (2000) New Engl. J. Med. 343:269-280; Tutuncu,et al. (2002) Clin. Exp. Rheumatol. 20(6 suppl. 28):s146-151. IL-4 playsarole in asthma, allergy, and COPD, while IL-13 is part of themechanisms of asthma and allergy, COPD, rheumatoid arthritis, IBD, suchas Crohn's disease and ulcerative colitis, and skin disorders, e.g.,psoriasis or atopic dermatitis, see, e.g., Steinke, et al. (2001)Respir. Res. 2:66-70; Jeffery (2001) Novartis Found. Symp. 234:149-161;van der Pouw Kraan, et al. (2002) Genes Immunol. 3:436-439; Spadero, etal. (2002) Clin. Exp. Rheumatol. 20:213-216; Bouma, et al. (2003) Nat.Rev. Immunol 3:521-533; Van der Ploeg, et al. (1997) Clin. Exp. Immunol.109:526-532.

III. Nucleic Acids

This invention contemplates use of isolated nucleic acid or fragments,e.g., which encode these or closely related proteins, or fragmentsthereof, e.g., to encode a corresponding polypeptide, preferably onewhich is biologically active. In addition, this invention coversisolated or recombinant DNAs which encode combinations of such proteinsor polypeptides having characteristic sequences, e.g., of the DCRS5s(SEQ ID NO:2) or human p19 (SEQ ID NO:6) alone or in combination withothers such as an IL-12Rβ1 or p40, respectively (see Showe, et al.(1996) Ann. N.Y. Acad. Sci. 795:413-425; Gately, et al. (1998) Ann. Rev.Immunol. 16:495-521; GenBank U03187, NM_(—)005535) subunit. Typically,the nucleic acid is capable of hybridizing, under appropriateconditions, with a nucleic acid sequence segment of SEQ ID NOs: 1 or 5,but preferably not with a corresponding segment of other receptorsdescribed in Table 1, i.e., hIL-6R gp130 or hIL-1Rbeta2. Saidbiologically active protein or polypeptide can be a full length protein,or fragment, and will typically have a segment of amino acid sequencehighly homologous, e.g., exhibiting significant stretches of identity,to one shown in SEQ ID NO:2. Further, this invention covers the use ofisolated or recombinant nucleic acid, or fragments thereof, which encodeproteins having fragments which are equivalent to the DCRS5 proteins,e.g., intracellular portions. The isolated nucleic acids can have therespective regulatory sequences in the 5′ and 3′ flanks, e.g.,promoters, enhancers, poly-A addition signals, and others from thenatural gene. Combinations, as described, are also provided, e.g.,comprising the DCRS5 with the IL-12Rβ1, or their extracellular ligandbinding portions as ligand antagonists. Diagnostic utilities are alsoclearly important, e.g., of polymorphic or other variants.

An “isolated” nucleic acid, e.g., an RNA, DNA, or a mixed polymer, whichis substantially pure, e.g., separated from other components whichnaturally accompany a native sequence, such as ribosomes, polymerases,and flanking genomic sequences from the originating species. The termembraces a nucleic acid sequence which has been removed from itsnaturally occurring environment, and includes recombinant or cloned DNAisolates, which are thereby distinguishable from naturally occurringcompositions, and chemically synthesized analogs or analogs biologicallysynthesized by heterologous systems. A substantially pure moleculeincludes isolated forms of the molecule, either completely orsubstantially pure.

An isolated nucleic acid will generally be a homogeneous composition ofmolecules, but will, in some embodiments, contain heterogeneity,preferably minor. This heterogeneity is typically found at the polymerends or portions not critical to a desired biological function oractivity.

A “recombinant” nucleic acid is typically defined either by its methodof production or its structure. In reference to its method ofproduction, e.g., a product made by a process, the process is use ofrecombinant nucleic acid techniques, e.g., involving human interventionin the nucleotide sequence. Typically this intervention involves invitro manipulation, although under certain circumstances it may involvemore classical animal breeding techniques. Alternatively, it can be anucleic acid made by generating a sequence comprising fusion of twofragments which are not naturally contiguous to each other, but is meantto exclude products of nature, e.g., naturally occurring mutants asfound in their natural state. Thus, e.g., products made by transformingcells with an unnaturally occurring vector is encompassed, as arenucleic acids comprising sequence derived using any syntheticoligonucleotide process. Such a process is often done to replace, e.g.,a codon with a redundant codon encoding the same or a conservative aminoacid, while typically introducing or removing a restriction enzymesequence recognition site, or for some structure-function analysis.Alternatively, the process is performed to join together nucleic acidsegments of desired functions to generate a single genetic entitycomprising a desired combination of functions not found in the commonlyavailable natural forms, e.g., encoding a fusion protein. Restrictionenzyme recognition sites are often the target of such artificialmanipulations, but other site specific targets, e.g., promoters, DNAreplication sites, regulation sequences, control sequences, or otheruseful features may be incorporated by design. A similar concept isintended for a recombinant, e.g., fusion, polypeptide. This will includea dimeric repeat or fusion of the DCRS5 with IL-12Rβ1 subunit.Specifically included are synthetic nucleic acids which, by genetic coderedundancy, encode equivalent polypeptides to fragments of DCRS5 andfusions of sequences from various different related molecules, e.g.,other cytokine family members.

A “fragment” in a nucleic acid context is a contiguous segment of atleast about 17 nucleotides, generally at least 21 nucleotides, moregenerally at least 25 nucleotides, ordinarily at least 30 nucleotides,more ordinarily at least 35 nucleotides, often at least 39 nucleotides,more often at least 45 nucleotides, typically at least 50 nucleotides,more typically at least 55 nucleotides, usually at least 60 nucleotides,more usually at least 66 nucleotides, preferably at least 72nucleotides, more preferably at least 79 nucleotides, and inparticularly preferred embodiments will be at least 85 or morenucleotides, including 90, 100, 120, 140, 160, 180, 200, etc. Typically,fragments of different genetic sequences can be compared to one anotherover appropriate length stretches, particularly defined segments such asthe domains described below.

A nucleic acid which codes for the DCRS5 or p19 will be particularlyuseful to identify genes, mRNA, and cDNA species which code for itselfor closely related proteins, as well as DNAs which code for polymorphic,allelic, or other genetic variants, e.g., from different individuals orrelated species. Preferred probes for such screens are those regions ofthe receptor which are conserved between different polymorphic variantsor which contain nucleotides which lack specificity, and will preferablybe full length or nearly so. In other situations, polymorphic variantspecific sequences will be more useful. Combinations of polymorphicvariants of DCRS5 with variants of IL-12Rβ1 may also be diagnosed.

Substantial identity in the nucleic acid sequence comparison contextmeans either that the segments, or their complementary strands, whencompared, are identical when optimally aligned, with appropriatenucleotide insertions or deletions, in at least about 60% of thenucleotides, generally at least 66%, ordinarily at least 71%, often atleast 76%, more often at least 80%, usually at least 84%, more usuallyat least 88%, typically at least 91%, more typically at least about 93%,preferably at least about 95%, more preferably at least about 96 to 98%or more, and in particular embodiments, as high at about 99% or more ofthe nucleotides, including, e.g., segments encoding structural domainsor other segments described. Alternatively, substantial identity willexist when the segments will hybridize under selective hybridizationconditions, to a strand or its complement, typically using a sequencederived from SEQ ID NOs: 1 or 5. Typically, selective hybridization willoccur when there is at least about 55% homology over a stretch of atleast about 14 nucleotides, more typically at least about 65%,preferably at least about 75%, and more preferably at least about 90%,see, e.g., Kanehisa (1984) Nucl. Acids Res. 12:203-213. The length ofhomology comparison, as described, may be over longer stretches, and incertain embodiments will be over a stretch of at least about 17nucleotides, generally at least about 20 nucleotides, ordinarily atleast about 24 nucleotides, usually at least about 28 nucleotides,typically at least about 32 nucleotides, more typically at least about40 nucleotides, preferably at least about 50 nucleotides, and morepreferably at least about 75 to 100 or more nucleotides. This includes,e.g., 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, etc., and otherlengths.

Stringent conditions, in referring to homology in the hybridizationcontext, will be stringent combined conditions of salt, temperature,organic solvents, and other parameters typically controlled inhybridization conditions. Stringent temperature conditions will usuallyinclude temperatures in excess of about 30° C., more usually in excessof about 37° C., typically in excess of about 45° C., more typically inexcess of about 55° C., preferably in excess of about 65° C., and morepreferably in excess of about 70° C. Stringent salt conditions willordinarily be less than about 500 mM, usually less than about 400 mM,more usually less than about 300 mM, typically less than about 200 mM,preferably less than about 100 mM, and more preferably less than about80 mM, even down to less than about 50 or 20 mM. However, thecombination of parameters is much more important than the measure of anysingle parameter, see, e.g., Wetmur and Davidson (1968) J. Mol. Biol.31:349-370.

The isolated DNA can be readily modified by nucleotide substitutions,nucleotide deletions, nucleotide insertions, and inversions ofnucleotide stretches. These modifications result in novel DNA sequenceswhich encode this protein or its derivatives. These modified sequencescan be used to produce mutant proteins (muteins) or to enhance theexpression of variant species. Enhanced expression may involve geneamplification, increased transcription, increased translation, and othermechanisms. Such mutant DCRS5s have an amino acid sequence which differsfrom that of other cytokine receptor-like proteins as found in nature,whether by way of deletion, substitution, or insertion. In particular,“site specific mutant DCRS5” encompasses a protein having substantialsequence identity with a protein of SEQ ID NO:2, and typically sharesmost of the biological activities or effects of the forms disclosedherein. Various natural polymorphic variant sequences will also beidentified.

Although site specific mutation sites are predetermined, mutants neednot be site specific. Mammalian DCRS5 mutagenesis can be achieved bymaking amino acid insertions or deletions in the gene, coupled withexpression. Substitutions, deletions, insertions, or many combinationsmay be generated to arrive at a final construct. Insertions includeamino- or carboxy terminal fusions. Random mutagenesis can be conductedat a target codon and the expressed mammalian DCRS5 mutants can then bescreened for the desired activity, providing some aspect of astructure-activity relationship. Methods for making substitutionmutations at predetermined sites in DNA having a known sequence are wellknown in the art, e.g., by M13 primer mutagenesis. See also Sambrook, etal. (1989) and Ausubel, et al. (1987 and periodic Supplements).Particularly useful constructs will be extracellular portions of theDCRS5 associated with IL-12Rβ1 segments.

The mutations in the DNA normally should not place coding sequences outof reading frames and preferably will not create complementary regionsthat could hybridize to produce secondary mRNA structure such as loopsor hairpins.

The phosphoramidite method described by Beaucage and Carruthers (1981)Tetra. Letts. 22:1859-1862, will produce suitable synthetic DNAfragments. A double stranded fragment will often be obtained either bysynthesizing the complementary strand and annealing the strand togetherunder appropriate conditions or by adding the complementary strand usingDNA polymerase with an appropriate primer sequence.

Polymerase chain reaction (PCR) techniques can often be applied inmutagenesis. Alternatively, mutagenesis primers are commonly usedmethods for generating defined mutations at predetermined sites. See,e.g., Innis, et al. (eds.) (1990) PCR Protocols: A Guide to Methods andApplications Academic Press, San Diego, Calif.; and Dieffenbach andDveksler (eds.) (1995) PCR Primer: A Laboratory Manual Cold SpringHarbor Press, CSH, NY.

Certain embodiments of the invention are directed to combinationcompositions comprising the receptor sequences described. In otherembodiments, functional portions of the sequences may be joined toencode fusion proteins. In other forms, variants of the describedsequences may be substituted.

IV. Proteins, Peptides

As described above, the present invention encompasses primate DCRS5 andp19, e.g., whose sequences are disclosed in SEQ ID NOs:1-2 and 5-6, anddescribed above. Allelic and other variants are also contemplated,including, e.g., fusion proteins combining portions of such sequenceswith others, including, e.g., IL-12Rβ1, p40, epitope tags, andfunctional domains.

The present invention also provides recombinant proteins, e.g.,heterologous fusion proteins using segments from these primate or rodentproteins. A heterologous fusion protein is a fusion of proteins orsegments which are naturally not normally fused in the same manner.Thus, the fusion product of a DCRS5 with another cytokine receptor is acontinuous protein molecule having sequences fused in a typical peptidelinkage, typically made as a single translation product and exhibitingproperties, e.g., sequence or antigenicity, derived from each sourcepeptide. A similar concept applies to heterologous nucleic acidsequences. Combinations of various designated proteins into complexesare also provided.

In addition, new constructs may be made from combining similarfunctional or structural domains from other related proteins, e.g.,cytokine receptors or Toll-like receptors, including species variants.For example, ligand-binding or other segments may be “swapped” betweendifferent new fusion polypeptides or fragments, see, e.g., Cunningham,et al. (1989) Science 243:1330-1336; O'Dowd, et al. (1988) J. Biol.Chem. 263:15985-15992. Thus, new chimeric polypeptides exhibiting newcombinations of specificities will result from the functional linkage ofreceptor-binding specificities. For example, the ligand binding domainsfrom other related receptor molecules may be added or substituted forother domains of this or related proteins. The resulting protein willoften have hybrid function and properties. For example, a fusion proteinmay include a targeting domain which may serve to provide sequesteringof the fusion protein to a particular subcellular organelle.

Candidate fusion partners and sequences can be selected from varioussequence data bases, e.g., GenBank, c/o IntelliGenetics, Mountain View,Calif.; and GCG, University of Wisconsin Biotechnology Computing Group,Madison, Wis. In particular, combinations of polypeptide sequencesprovided in SEQ ID NOs:2-4 are particularly preferred. Variant forms ofthe proteins may be substituted in the described combinations.

The present invention particularly provides muteins which bindcytokine-like ligands, and/or which are affected in signal transduction.Structural alignment of human DCRS5 with other members of the cytokinereceptor family show conserved features/residues (Table 1). Alignment ofthe human DCRS5 sequence with other members of the cytokine receptorfamily indicates various structural and functionally shared features.See also, Bazan, et al. (1996) Nature 379:591; Lodi, et al. (1994)Science 263:1762-1766; Sayle and Milner-White (1995) TIBS 20:374-376;and Gronenberg, et al. (1991) Protein Engineering 4:263-269.

Substitutions with either mouse sequences or human sequences areparticularly preferred. Conversely, conservative substitutions away fromthe ligand binding interaction regions will probably preserve mostsignaling activities; and conservative substitutions away from theintracellular domains will probably preserve most ligand bindingproperties.

“Derivatives” of the primate DCRS5 include amino acid sequence mutants,glycosylation variants, metabolic derivatives and covalent oraggregative conjugates with other chemical moieties. Covalentderivatives can be prepared by linkage of functionalities to groupswhich are found in the DCRS5 amino acid side chains or at the N-termini,e.g., by means which are well known in the art. These derivatives caninclude, without limitation, aliphatic esters or amides of the carboxylterminus, or of residues containing carboxyl side chains, O-acylderivatives of hydroxyl group containing residues, and N-acylderivatives of the amino terminal amino acid or amino group containingresidues, e.g., lysine or arginine. Acyl groups are selected from thegroup of alkyl moieties, including C3 to C18 normal alkyl, therebyforming alkanoyl aroyl species.

In particular, glycosylation alterations are included, e.g., made bymodifying the glycosylation patterns of a polypeptide during itssynthesis and processing, or in further processing steps. Particularlypreferred means for accomplishing this are by exposing the polypeptideto glycosylating enzymes derived from cells which normally provide suchprocessing, e.g., mammalian glycosylation enzymes. Deglycosylationenzymes are also contemplated. Also embraced are versions of the sameprimary amino acid sequence which have other minor modifications,including phosphorylated amino acid residues, e.g., phosphotyrosine,phosphoserine, or phosphothreonine.

A major group of derivatives are covalent conjugates of the receptors orfragments thereof with other proteins of polypeptides. These derivativescan be synthesized in recombinant culture such as N terminal fusions orby the use of agents known in the art for their usefulness in crosslinking proteins through reactive side groups. Preferred derivatizationsites with cross linking agents are at free amino groups, carbohydratemoieties, and cysteine residues.

Fusion polypeptides between the receptors and other homologous orheterologous proteins are also provided. Homologous polypeptides may befusions between different receptors, resulting in, for instance, ahybrid protein exhibiting binding specificity for multiple differentcytokine ligands, or a receptor which may have broadened or weakenedspecificity of substrate effect. Likewise, heterologous fusions may beconstructed which would exhibit a combination of properties oractivities of the derivative proteins. Typical examples are fusions of areporter polypeptide, e.g., luciferase, with a segment or domain of areceptor, e.g., a ligand-binding segment, so that the presence orlocation of a desired ligand may be easily determined, see, e.g., U.S.Pat. No. 4,859,609 issued to Dull, et al. Other gene fusion partnersinclude glutathione-S-transferase (GST), bacterial β-galactosidase,trpE, Protein A, β-lactamase, alpha amylase, alcohol dehydrogenase, andyeast alpha mating factor, see, e.g., Godowski, et al. (1988) Science241:812-816. Labeled proteins will often be substituted in the describedcombinations of proteins.

The phosphoramidate method of Beaucage and Carruthers (1981) Tetra.Letts. 22:1859-1862, will produce suitable synthetic DNA fragments. Adouble stranded fragment will often be obtained either by synthesizingthe complementary strand and annealing the strand together underappropriate conditions or by adding the complementary strand using DNApolymerase with an appropriate primer sequence.

Such polypeptides may also have amino acid residues which have beenchemically modified by phosphorylation, sulfonation, biotinylation, orthe addition or removal of other moieties, particularly those which havemolecular shapes similar to phosphate groups. In some embodiments, themodifications will be useful labeling reagents, or serve as purificationtargets, e.g., affinity ligands.

Fusion proteins will typically be made by either recombinant nucleicacid methods or by synthetic polypeptide methods. Techniques for nucleicacid manipulation and expression are described generally, for example,in Sambrook, et al. (1989) Molecular Cloning: A Laboratory Manual (2ded.), Vols. 1 3, Cold Spring Harbor Laboratory, and Ausubel, et al.(eds.) (1987 and periodic supplements) Current Protocols in MolecularBiology, Greene/Wiley, New York. Techniques for synthesis ofpolypeptides are described, see, e.g., Merrifield (1963) J. Amer. Chem.Soc. 85:2149-2156; Merrifield (1986) Science 232: 341-347; Atherton, etal. (1989) Solid Phase Peptide Synthesis: A Practical Approach, IRLPress, Oxford. See also Dawson, et al. (1994) Science 266:776-779 formethods to make larger polypeptides.

This invention also contemplates the use of derivatives of a DCRS5 otherthan variations in amino acid sequence or glycosylation. Suchderivatives may involve covalent or aggregative association withchemical moieties. These derivatives generally fall into three classes:(1) salts, (2) side chain and terminal residue covalent modifications,and (3) adsorption complexes, e.g., with cell membranes. Such covalentor aggregative derivatives are useful as immunogens, as reagents inimmunoassays, or in purification methods such as for affinitypurification of a receptor or other binding molecule, e.g., an antibody.For example, a cytokine ligand can be immobilized by covalent bonding toa solid support such as cyanogen bromide activated Sepharose®, bymethods which are well known in the art, or adsorbed onto polyolefinsurfaces, with or without glutaraldehyde cross linking, for use in theassay or purification of a cytokine receptor, antibodies, or othersimilar molecules. The ligand can also be labeled with a detectablegroup, e.g., radioiodinated by the chloramine T procedure, covalentlybound to rare earth chelates, or conjugated to another fluorescentmoiety for use in diagnostic assays.

A combination, e.g., including a DCRS5, of this invention can be used asan immunogen for the production of antisera or antibodies specific,e.g., capable of distinguishing between other cytokine receptor familymembers, for the combinations described. The complexes can be used toscreen monoclonal antibodies or antigen-binding fragments prepared byimmunization with various forms of impure preparations containing theprotein. In particular, the term “antibodies” also encompasses antigenbinding fragments of natural antibodies, e.g., Fab, Fab2, Fv, etc. Thepurified DCRS5 can also be used as a reagent to detect antibodiesgenerated in response to the presence of elevated levels of expression,or immunological disorders which lead to antibody production to theendogenous receptor. Additionally, DCRS5 fragments may also serve asimmunogens to produce the antibodies of the present invention, asdescribed immediately below. For example, this invention contemplatesantibodies having binding affinity to or being raised against SEQ IDNO:2, fragments thereof, or various homologous peptides. In particular,this invention contemplates antibodies having binding affinity to, orhaving been raised against, specific fragments which are predicted tobe, or actually are, exposed at the exterior protein surface of thenative DCRS5. Complexes of combinations of proteins will also be useful,and antibody preparations thereto can be made.

In certain other embodiments, soluble constructs, e.g., of theextracellular ligand binding segments of the DCRS5 with the IL-12Rβ1 maybe binding compositions for the ligand and may be useful as eitherligand antagonists, or as antigens to block ligand mediated signaling.Such may be useful either diagnostically, e.g., for histology labelingfor ligand, or therapeutically, e.g., as ligand antagonists.

The blocking of physiological response to the receptor ligands mayresult from the inhibition of binding of the ligand to the receptor,likely through competitive inhibition. Thus, in vitro assays of thepresent invention will often use antibodies or antigen binding segmentsof these antibodies, soluble receptor constructs, or fragments attachedto solid phase substrates. These assays will also allow for thediagnostic determination of the effects of either ligand binding regionmutations and modifications, or other mutations and modifications, e.g.,which affect signaling or enzymatic function.

This invention also contemplates the use of competitive drug screeningassays, e.g., where neutralizing antibodies to the receptor complexes orfragments compete with a test compound for binding to a ligand or otherantibody. In this manner, the neutralizing antibodies or fragments canbe used to detect the presence of a polypeptide which shares one or morebinding sites to a receptor and can also be used to occupy binding siteson a receptor that might otherwise bind a ligand. Soluble receptorconstructs combining the extracellular, or ligand binding, domains ofthe DCRS5 or the IL-12Rβ1, may be useful antagonists for competitivebinding of p40/p19 ligand.

V. Making Nucleic Acids and Protein

DNA which encodes the protein or fragments thereof can be obtained bychemical synthesis, screening cDNA libraries, or by screening genomiclibraries prepared from a wide variety of cell lines or tissue samples.Natural sequences can be isolated using standard methods and thesequences provided herein, e.g., SEQ ID NO:2. Other species counterpartscan be identified by hybridization techniques, or by various PCRtechniques, combined with or by searching in sequence databases, e.g.,GenBank.

This DNA can be expressed in a wide variety of host cells for thesynthesis of a full length receptor or fragments which can in turn, forexample, be used to generate polyclonal or monoclonal antibodies; forbinding studies; for construction and expression of modified ligandbinding or kinase/phosphatase domains; and for structure/functionstudies. Variants or fragments can be expressed in host cells that aretransformed or transfected with appropriate expression vectors. Thesemolecules can be substantially free of protein or cellular contaminants,other than those derived from the recombinant host, and therefore areparticularly useful in pharmaceutical compositions when combined with apharmaceutically acceptable carrier and/or diluent. The protein, orportions thereof, may be expressed as fusions with other proteins.Combinations of the described proteins, or nucleic acids encoding them,are particularly interesting.

Expression vectors are typically self replicating DNA or RNA constructscontaining the desired receptor gene, its fragments, or combinationgenes, usually operably linked to suitable genetic control elements thatare recognized in a suitable host cell. These control elements arecapable of effecting expression within a suitable host. Multiple genesmay be coordinately expressed, and may be on a polycistronic message.The specific type of control elements necessary to effect expressionwill depend upon the eventual host cell used. Generally, the geneticcontrol elements can include a prokaryotic promoter system or aeukaryotic promoter expression control system, and typically include atranscriptional promoter, an optional operator to control the onset oftranscription, transcription enhancers to elevate the level of mRNAexpression, a sequence that encodes a suitable ribosome binding site,and sequences that terminate transcription and translation. Expressionvectors also usually contain an origin of replication that allows thevector to replicate independently of the host cell.

The vectors of this invention include those which contain DNA whichencodes a combination of proteins, as described, or a biologicallyactive equivalent polypeptide. The DNA can be under the control of aviral promoter and can encode a selection marker. This invention furthercontemplates use of such expression vectors which are capable ofexpressing eukaryotic cDNAs coding for such proteins in a prokaryotic oreukaryotic host, where the vector is compatible with the host and wherethe eukaryotic cDNAs are inserted into the vector such that growth ofthe host containing the vector expresses the cDNAs in question. Usually,expression vectors are designed for stable replication in their hostcells or for amplification to greatly increase the total number ofcopies of the desirable gene(s) per cell. It is not always necessary torequire that an expression vector replicate in a host cell, e.g., it ispossible to effect transient expression of the protein or its fragmentsin various hosts using vectors that do not contain a replication originthat is recognized by the host cell. It is also possible to use vectorsthat cause integration of the protein encoding portions into the hostDNA by recombination.

Vectors, as used herein, comprise plasmids, viruses, bacteriophage,integratable DNA fragments, and other vehicles which enable theintegration of DNA fragments into the genome of the host. Expressionvectors are specialized vectors which contain genetic control elementsthat effect expression of operably linked genes. Plasmids are the mostcommonly used form of vector but all other forms of vectors which servean equivalent function and which are, or become, known in the art aresuitable for use herein, see, e.g., Pouwels, et al. (1985 andSupplements) Cloning Vectors: A Laboratory Manual, Elsevier, N.Y., andRodriguez, et al. (eds.) (1988) Vectors: A Survey of Molecular CloningVectors and their Uses, Buttersworth, Boston.

Transformed cells are cells, preferably mammalian, that have beentransformed or transfected with vectors constructed using recombinantDNA techniques. Transformed host cells usually express the desiredproteins, but for purposes of cloning, amplifying, and manipulating itsDNA, do not need to express the subject proteins. This invention furthercontemplates culturing transformed cells in a nutrient medium, thuspermitting the proteins to accumulate. The proteins can be recovered,either from the culture or, in certain instances, from the culturemedium.

For purposes of this invention, nucleic sequences are operably linkedwhen they are functionally related to each other. For example, DNA for apresequence or secretory leader is operably linked to a polypeptide ifit is expressed as a preprotein or participates in directing thepolypeptide to the cell membrane or in secretion of the polypeptide. Apromoter is operably linked to a coding sequence if it controls thetranscription of the polypeptide; a ribosome binding site is operablylinked to a coding sequence if it is positioned to permit translation.Usually, operably linked means contiguous and in reading frame, however,certain genetic elements such as repressor genes are not contiguouslylinked but still bind to operator sequences that in turn controlexpression.

Suitable host cells include prokaryotes, lower eukaryotes, and highereukaryotes. Prokaryotes include both gram negative and gram positiveorganisms, e.g., E. coli and B. subtilis. Lower eukaryotes includeyeasts, e.g., S. cerevisiae and Pichia, and species of the genusDictyostelium. Higher eukaryotes include established tissue culture celllines from animal cells, both of non mammalian origin, e.g., insectcells, and birds, and of mammalian origin, e.g., human, primates, androdents.

Prokaryotic host vector systems include a wide variety of vectors formany different species. As used herein, E. coli and its vectors will beused generically to include equivalent vectors used in otherprokaryotes. A representative vector for amplifying DNA is pBR322 ormany of its derivatives. Vectors that can be used to express thereceptor or its fragments include, but are not limited to, such vectorsas those containing the lac promoter (pUC series); trp promoter (pBR322trp); Ipp promoter (the pIN series); lambda pP or pR promoters (pOTS);or hybrid promoters such as ptac (pDR540), see, e.g., Brosius, et al.(1988) “Expression Vectors Employing Lambda, and Ipp derived Promoters”,in Vectors: A Survey of Molecular Cloning Vectors and Their Uses,(Rodriguez and Denhardt, eds.), Buttersworth, Boston, Chapter 10, pp.205 236.

Lower eukaryotes, e.g., yeasts and Dictyostelium, may be transformedwith DCRS5 sequence containing vectors. For purposes of this invention,the most common lower eukaryotic host is the baker's yeast,Saccharomyces cerevisiae. It will be used to generically represent lowereukaryotes although a number of other strains and species are alsoavailable. Yeast vectors typically consist of a replication origin(unless of the integrating type), a selection gene, a promoter, DNAencoding the receptor or its fragments, and sequences for translationtermination, polyadenylation, and transcription termination. Suitableexpression vectors for yeast include such constitutive promoters as 3phosphoglycerate kinase and various other glycolytic enzyme genepromoters or such inducible promoters as the alcohol dehydrogenase 2promoter or metallothionine promoter. Suitable vectors includederivatives of the following types: self replicating low copy number(such as the YRp series), self replicating high copy number (such as theYEp series); integrating types (such as the YIp series), or minichromosomes (such as the YCp series).

Higher eukaryotic tissue culture cells are normally the preferred hostcells for expression of the functionally active interleukin or receptorproteins. In principle, many higher eukaryotic tissue culture cell linesare workable, e.g., insect baculovirus expression systems, whether froman invertebrate or vertebrate source. However, mammalian cells arepreferred. Transformation or transfection and propagation of such cellshas become a routine procedure. Examples of useful cell lines includeHeLa cells, Chinese hamster ovary (CHO) cell lines, baby rat kidney(BRK) cell lines, insect cell lines, bird cell lines, and monkey (COS)cell lines. Expression vectors for such cell lines usually include anorigin of replication, a promoter, a translation initiation site, RNAsplice sites (if genomic DNA is used), a polyadenylation site, and atranscription termination site. These vectors also usually contain aselection gene or amplification gene. Suitable expression vectors may beplasmids, viruses, or retroviruses carrying promoters derived, e.g.,from such sources as from adenovirus, SV40, parvoviruses, vacciniavirus, or cytomegalovirus. Representative examples of suitableexpression vectors include pcDNA1; pCD, see Okayama, et al. (1985) Mol.Cell. Biol. 5:1136 1142; pMC1neo PolyA, see Thomas, et al. (1987) Cell51:503 512; and a baculovirus vector such as pAC 373 or pAC 610.

For secreted proteins and some membrane proteins, an open reading frameusually encodes a polypeptide that consists of a mature or secretedproduct covalently linked at its N-terminus to a signal peptide. Thesignal peptide is cleaved prior to secretion of the mature, or active,polypeptide. The cleavage site can be predicted with a high degree ofaccuracy from empirical rules, e.g., von-Heijne (1986) Nucleic AcidsResearch 14:4683-4690 and Nielsen, et al. (1997) Protein Eng. 10:1-12,and the precise amino acid composition of the signal peptide often doesnot appear to be critical to its function, e.g., Randall, et al. (1989)Science 243:1156-1159; Kaiser et al. (1987) Science 235:312-317. Themature proteins of the invention can be readily determined usingstandard methods.

It will often be desired to express these polypeptides in a system thatprovides a specific or defined glycosylation pattern. In this case, theusual pattern will be that provided naturally by the expression system.However, the pattern will be modifiable by exposing the polypeptide,e.g., an unglycosylated form, to appropriate glycosylating proteinsintroduced into a heterologous expression system. For example, thereceptor gene may be co-transformed with one or more genes encodingmammalian or other glycosylating enzymes. Using this approach, certainmammalian glycosylation patterns will be achievable in prokaryote orother cells. Expression in prokaryote cells will typically lead tounglycosylated forms of protein.

The source of DCRS5 can be a eukaryotic or prokaryotic host expressingrecombinant DCRS5, such as is described above. The source can also be acell line, but other mammalian cell lines are also contemplated by thisinvention, with the preferred cell line being from the human species.

The primate DCRS5, fragments, or derivatives thereof can be prepared byconventional processes for synthesizing peptides. These includeprocesses such as are described in Stewart and Young (1984) Solid PhasePeptide Synthesis, Pierce Chemical Co., Rockford, Ill.; Bodanszky andBodanszky (1984) The Practice of Peptide Synthesis, Springer Verlag, NewYork; Bodanszky (1984) The Principles of Peptide Synthesis, SpringerVerlag, New York. For example, an azide process, an acid chlorideprocess, an acid anhydride process, a mixed anhydride process, an activeester process (for example, p nitrophenyl ester, N hydroxysuccinimideester, or cyanomethyl ester), a carbodiimidazole process, an oxidativereductive process, or a dicyclohexylcarbodiimide (DCCD) additive processcan be used. Solid phase and solution phase syntheses are bothapplicable to the foregoing processes. Similar techniques can be usedwith partial DCRS5 sequences.

The DCRS5 proteins, fragments, or derivatives are suitably prepared inaccordance with the above processes as typically employed in peptidesynthesis, generally either by a so called stepwise process whichcomprises condensing an amino acid to the terminal amino acid, one byone in sequence, or by coupling peptide fragments to the terminal aminoacid. Amino groups that are not being used in the coupling reactiontypically must be protected to prevent coupling at an incorrectlocation.

If a solid phase synthesis is adopted, the C terminal amino acid isbound to an insoluble carrier or support through its carboxyl group. Theinsoluble carrier is not particularly limited as long as it has abinding capability to a reactive carboxyl group. Examples of suchinsoluble carriers include halomethyl resins, such as chloromethyl resinor bromomethyl resin, hydroxymethyl resins, phenol resins, tertalkyloxycarbonylhydrazidated resins, and the like.

An amino group protected amino acid is bound in sequence throughcondensation of its activated carboxyl group and the reactive aminogroup of the previously formed peptide or chain, to synthesize thepeptide step by step. After synthesizing the complete sequence, thepeptide is split off from the insoluble carrier to produce the peptide,see, e.g., Merrifield, et al. (1963) J. Am. Chem. Soc. 85:2149 2156.

The prepared protein and fragments thereof can be isolated and purifiedfrom the reaction mixture by means of peptide separation, e.g., byextraction, precipitation, electrophoresis, various forms ofchromatography, immunoaffinity, and the like. The receptors of thisinvention can be obtained in varying degrees of purity depending upondesired uses. Purification can be accomplished by use of the proteinpurification techniques disclosed herein, or by the use of theantibodies herein described in methods of immunoabsorbant affinitychromatography. This immunoabsorbant affinity chromatography is carriedout by first linking the antibodies to a solid support and thencontacting the linked antibodies with solubilized lysates of appropriatecells, lysates of other cells expressing the receptor, or lysates orsupernatants of cells producing the protein as a result of DNAtechniques.

Generally, the purified protein will be at least about 40% pure,ordinarily at least about 50% pure, usually at least about 60% pure,typically at least about 70% pure, more typically at least about 80%pure, preferable at least about 90% pure and more preferably at leastabout 95% pure, and in particular embodiments, 97%-99% or more. Puritywill usually be on a weight basis, but can also be on a molar basis.Different assays will be applied as appropriate. Individual proteins maybe purified and thereafter combined.

VI. Antibodies

Antibodies can be raised to the various mammalian, e.g., primate DCRS5proteins and fragments thereof, both in naturally occurring native formsand in their recombinant forms, the difference being that antibodies tothe active receptor are more likely to recognize epitopes which are onlypresent in the native conformations. Antibodies recognizing epitopespresented by the combination, e.g., functionally, of the DCRS5 with theIL-12Rβ1 are also contemplated. Denatured antigen detection can also beuseful in, e.g., Western analysis. Anti-idiotypic antibodies are alsocontemplated, which would be useful as agonists or antagonists of anatural receptor or an antibody.

Antibodies, including binding fragments and single chain versions,against predetermined fragments of the protein can be raised byimmunization of animals with conjugates of the fragments withimmunogenic proteins. Monoclonal antibodies are prepared from cellssecreting the desired antibody. These antibodies can be screened forbinding to normal or defective protein, or screened for agonistic orantagonistic activity. These monoclonal antibodies will usually bindwith at least a KD of about 1 mM, more usually at least about 300 μM,typically at least about 100 μM, more typically at least about 30 μM,preferably at least about 10 μM, and more preferably at least about 3 μMor better.

The antibodies, including antigen binding fragments, of this inventioncan have significant diagnostic or therapeutic value. They can be potentantagonists that bind to the receptor and inhibit binding to ligand orinhibit the ability of the receptor to elicit a biological response,e.g., act on its substrate. They also can be useful as non neutralizingantibodies and can be coupled to toxins or radionuclides to bindproducing cells, or cells localized to the source of the interleukin.Further, these antibodies can be conjugated to drugs or othertherapeutic agents, either directly or indirectly by means of a linker.

The antibodies of this invention can also be useful in diagnosticapplications. As capture or non neutralizing antibodies, they might bindto the receptor without inhibiting ligand or substrate binding. Asneutralizing antibodies, they can be useful in competitive bindingassays. They will also be useful in detecting or quantifying ligand.They may be used as reagents for Western blot analysis, or forimmunoprecipitation or immunopurification of the respective protein.Likewise, nucleic acids and proteins may be immobilized to solidsubstrates for affinity purification or detection methods. Thesubstrates may be, e.g., solid resin beads or sheets of plastic.

Protein fragments may be joined to other materials, particularlypolypeptides, as fused or covalently joined polypeptides to be used asimmunogens. Mammalian cytokine receptors and fragments may be fused orcovalently linked to a variety of immunogens, such as keyhole limpethemocyanin, bovine serum albumin, tetanus toxoid, etc. Methods forpreparing polyclonal antisera are described, see, e.g., Microbiology(1969) Hoeber Medical Division, Harper and Row; Landsteiner (1962)Specificity of Serological Reactions, Dover Publications, New York;Williams, et al. (1967) Methods in Immunology and Immunochemistry, Vol.1, Academic Press, New York. A typical method involves hyperimmunizationof an animal with an antigen. The blood of the animal is then collectedshortly after the repeated immunizations and the gamma globulin isisolated.

In some instances, it is desirable to prepare monoclonal antibodies fromvarious mammalian hosts, such as mice, rodents, primates, humans, etc.Description of techniques for preparing such monoclonal antibodies maybe found in, e.g., Stites, et al. (eds.) Basic and Clinical Immunology(4th ed.), Lange Medical Publications, Los Altos, Calif., and referencescited therein; Harlow and Lane (1988) Antibodies: A Laboratory Manual,Cold Spring Harbor Press, Cold Spring Harbor, N.Y.; Goding (1986)Monoclonal Antibodies: Principles and Practice (2d ed.) Academic Press,New York; and particularly in Kohler and Milstein (1975) Nature 256: 495497, which discusses one method of generating monoclonal antibodies.This method involves injecting an animal with an immunogen. The animalis then sacrificed and cells taken from its spleen, which are then fusedwith myeloma cells. The result is a hybrid cell or “hybridoma” that iscapable of reproducing in vitro. The population of hybridomas is thenscreened to isolate individual clones, each of which secrete a singleantibody species to the immunogen. In this manner, the individualantibody species obtained are the products of immortalized and clonedsingle B cells from the immune animal generated in response to aspecific site recognized on the immunogenic substance.

Other suitable techniques involve in vitro exposure of lymphocytes tothe antigenic polypeptides or alternatively to selection of libraries ofantibodies in phage or similar vectors. See, Huse, et al. (1989) Science246:1275-1281; and Ward, et al. (1989) Nature 341:544-546. Thepolypeptides and antibodies of the present invention may be used with orwithout modification, including chimeric or humanized antibodies.Frequently, the polypeptides and antibodies will be labeled by joining,either covalently or non-covalently, a substance which provides for adetectable signal. Suitable labels include radionuclides, enzymes,substrates, cofactors, inhibitors, fluorescent moieties,chemiluminescent moieties, magnetic particles, and the like. Patents,teaching the use of such labels include U.S. Pat. Nos. 3,817,837;3,850,752; 3,939,350; 3,996,345; 4,277,437; 4,275,149; and 4,366,241.Also, recombinant or chimeric immunoglobulins may be produced, seeCabilly, U.S. Pat. No. 4,816,567; or made in transgenic mice, seeMendez, et al. (1997) Nature Genetics 15:146-156.

The antibodies of this invention can also be used for affinitychromatography in isolating the DCRS5 proteins or peptides. Columns canbe prepared where the antibodies are linked to a solid support, e.g.,particles, such as agarose, Sephadex®, or the like, where a cell lysatemay be passed through the column, the column washed, followed byincreasing concentrations of a mild denaturant, whereby the purifiedprotein will be released. Alternatively, the protein may be used topurify antibody. Appropriate cross absorptions or depletions may beapplied.

The antibodies may also be used to screen expression libraries forparticular expression products. Usually the antibodies used in such aprocedure will be labeled with a moiety allowing easy detection ofpresence of antigen by antibody binding.

Antibodies raised against a cytokine receptor will also be used to raiseanti-idiotypic antibodies. These will be useful in detecting ordiagnosing various immunological conditions related to expression of theprotein or cells which express the protein. They also will be useful asagonists or antagonists of the ligand, which may be competitive receptorinhibitors or substitutes for naturally occurring ligands. Certainantibodies to receptor subunits or combinations may serve as activatingantibodies, which may effect signaling thereby serving, e.g., as ligandagonists.

A cytokine receptor protein that specifically binds to or that isspecifically immunoreactive with an antibody generated against a definedimmunogen, such as an immunogen consisting of the amino acid sequence ofSEQ ID NO:2, is typically determined in an immunoassay. The immunoassaytypically uses a polyclonal antiserum which was raised, e.g., to aprotein of SEQ ID NO:2. This antiserum is selected to have lowcrossreactivity against other cytokine receptor family members, e.g.,IL-12Rβ receptor subunit or IL-6 receptor subunit gp 130, preferablyfrom the same species, and any such crossreactivity is removed byimmunoprecipitation prior to use in the immunoassay.

In order to produce antisera for use in an immunoassay, the protein,e.g., of SEQ ID NO:2, is isolated as described herein. For example,recombinant protein may be produced in a mammalian cell line. Anappropriate host, e.g., an inbred strain of mice such as Balb/c, isimmunized with the selected protein, typically using a standardadjuvant, such as Freund's adjuvant, and a standard mouse immunizationprotocol (see Harlow and Lane, supra). Alternatively, a syntheticpeptide derived from the sequences disclosed herein and conjugated to acarrier protein can be used an immunogen. Polyclonal sera are collectedand titered against the immunogen protein in an immunoassay, e.g., asolid phase immunoassay with the immunogen immobilized on a solidsupport. Polyclonal antisera with a titer of 10⁴ or greater are selectedand tested for their cross reactivity against other cytokine receptorfamily members, e.g., gp130 or IL-12Rβ1 using a competitive bindingimmunoassay such as the one described in Harlow and Lane, supra, atpages 570-573. Preferably at least two cytokine receptor family membersare used in this determination. These cytokine receptor family memberscan be produced as recombinant proteins and isolated using standardmolecular biology and protein chemistry techniques as described herein.

Immunoassays in the competitive binding format can be used for thecrossreactivity determinations. For example, the protein of SEQ ID NO:2can be immobilized to a solid support. Proteins added to the assaycompete with the binding of the antisera to the immobilized antigen. Theability of the above proteins to compete with the binding of theantisera to the immobilized protein is compared to the proteins, e.g.,of gp130 or IL-12Rβ2. The percent crossreactivity for the above proteinsis calculated. Those antisera with less than 10% crossreactivity witheach of the proteins listed above are selected and pooled. Thecross-reacting antibodies are then removed from the pooled antisera byimmunoabsorption with the above-listed proteins.

The immunoabsorbed and pooled antisera are then used in a competitivebinding immunoassay as described above to compare a second protein tothe immunogen protein (e.g., the DCRS5 like protein of SEQ ID NO:2). Inorder to make this comparison, the two proteins are each assayed at awide range of concentrations and the amount of each protein required toinhibit 50% of the binding of the antisera to the immobilized protein isdetermined. If the amount of the second protein required is less thantwice the amount of the protein of the selected protein or proteins thatis required, then the second protein is said to specifically bind to anantibody generated to the immunogen.

It is understood that these cytokine receptor proteins are members of afamily of homologous proteins that comprise many identified genes. For aparticular gene product, such as the DCRS5, the term refers not only tothe amino acid sequences disclosed herein, but also to other proteinsthat are allelic, non-allelic, or species variants. It is alsounderstood that the terms include normatural mutations introduced bydeliberate mutation using conventional recombinant technology such assingle site mutation, or by excising short sections of DNA encoding therespective proteins, or by substituting new amino acids, or adding newamino acids. Such minor alterations typically will substantiallymaintain the immunoidentity of the original molecule and/or itsbiological activity. Thus, these alterations include proteins that arespecifically immunoreactive with a designated naturally occurring DCRS5protein. The biological properties of the altered proteins can bedetermined by expressing the protein in an appropriate cell line andmeasuring the appropriate effect, e.g., upon transfected lymphocytes.Particular protein modifications considered minor would includeconservative substitution of amino acids with similar chemicalproperties, as described above for the cytokine receptor family as awhole. By aligning a protein optimally with the protein of the cytokinereceptors and by using the conventional immunoassays described herein todetermine immunoidentity, one can determine the protein compositions ofthe invention.

Moreover, antibodies against the receptor subunits may serve tosterically block ligand binding to the functional receptor. Suchantibodies may be raised to either subunit alone, or to the combinationof DCRS5 and IL-12R1. Antibody antagonists would result.

VII. Kits, Diagnostics, and Quantitation.

Both naturally occurring and recombinant forms of the cytokine receptorlike molecules of this invention are useful in kits and assay methods.For example, these methods would also be applied to screening forbinding activity, e.g., ligands for these proteins. Several methods ofautomating assays have been developed in recent years so as to permitscreening of tens of thousands of compounds per year, see, e.g., BIOMEKautomated workstation, Beckman Instruments, Palo Alto, Calif., Fodor, etal. (1991) Science 251:767-773. The latter describes means for testingbinding by a plurality of defined polymers synthesized on a solidsubstrate. The development of suitable assays to screen for a ligand oragonist/antagonist homologous proteins can be greatly facilitated by theavailability of large amounts of purified, soluble cytokine receptors inan active state such as is provided by this invention.

Purified DCRS5 can be coated directly onto plates for use in theaforementioned ligand screening techniques. However, non neutralizingantibodies to these proteins can be used as capture antibodies toimmobilize the respective receptor on the solid phase, useful, e.g., indiagnostic uses.

This invention also contemplates use of DCRS5 and/or p19, fragmentsthereof, peptides, and their fusion products in a variety of diagnostickits and methods for detecting the presence of the protein or itsligand. Alternatively, or additionally, antibodies against the moleculesmay be incorporated into the kits and methods. Typically the kit willhave a compartment containing either a DCRS5 and/or p19 peptide or genesegment or a reagent which recognizes one or the other. Typically,recognition reagents, in the case of peptide, would be a receptor orantibody, or in the case of a gene segment, would usually be ahybridization probe. Other kit components may include other proteins orreagents related to the p40, p19 (a.k.a. IL-B30), or IL-12Rβ1polypeptides of the ligand/receptor pairing.

A preferred kit for determining the concentration of DCRS5 in a samplewould typically comprise a labeled compound, e.g., ligand or antibody,having known binding affinity for DCRS5, a source of naturally occurringor recombinant DCRS5, as a positive control, and a means for separatingthe bound from free labeled compound, for example a solid phase forimmobilizing the DCRS5 in the test sample. Compartments containingreagents, and instructions, will normally be provided. Appropriatenucleic acid or protein containing kits are also provided.

Antibodies, including antigen binding fragments, specific for mammalianDCRS5 or a peptide fragment, or receptor fragments are useful indiagnostic applications to detect the presence of elevated levels ofligand and/or its fragments. Diagnostic assays may be homogeneous(without a separation step between free reagent and antibody-antigencomplex) or heterogeneous (with a separation step). Various commercialassays exist, such as radioimmunoassay (RIA), enzyme linkedimmunosorbent assay (ELISA), enzyme immunoassay (EIA), enzyme multipliedimmunoassay technique (EMIT), substrate labeled fluorescent immunoassay(SLFIA) and the like. For example, unlabeled antibodies can be employedby using a second antibody which is labeled and which recognizes theantibody to a cytokine receptor or to a particular fragment thereof,see, e.g., Harlow and Lane, supra, and Coligan (ed. 1991 and periodicsupplements) Current Protocols In Immunology Greene/Wiley, New York.

Anti-idiotypic antibodies may have similar use to serve as agonists orantagonists of cytokine receptors. These should be useful as therapeuticreagents under appropriate circumstances.

Frequently, the reagents for diagnostic assays are supplied in kits, soas to optimize the sensitivity of the assay. For the subject invention,depending upon the nature of the assay, the protocol, and the label,either labeled or unlabeled antibody, or labeled ligand is provided.This is usually in conjunction with other additives, such as buffers,stabilizers, materials necessary for signal production such assubstrates for enzymes, and the like. Preferably, the kit will alsocontain instructions for proper use and disposal of the contents afteruse. Typically the kit has compartments for each useful reagent, andwill contain instructions for proper use and disposal of reagents.Desirably, the reagents are provided as a dry lyophilized powder, wherethe reagents may be reconstituted in an aqueous medium havingappropriate concentrations for performing the assay.

The aforementioned constituents of the diagnostic assays may be usedwithout modification or may be modified in a variety of ways. Forexample, labeling may be achieved by covalently or non covalentlyjoining a moiety which directly or indirectly provides a detectablesignal. In many of these assays, a test compound, cytokine receptor, orantibodies thereto can be labeled either directly or indirectly.Possibilities for direct labeling include label groups: radiolabels suchas ¹²⁵I, enzymes (U.S. Pat. No. 3,645,090) such as peroxidase andalkaline phosphatase, and fluorescent labels (U.S. Pat. No. 3,940,475)capable of monitoring the change in fluorescence intensity, wavelengthshift, or fluorescence polarization. Possibilities for indirect labelinginclude biotinylation of one constituent followed by binding to avidincoupled to one of the above label groups.

There are also numerous methods of separating the bound from the freeligand, or alternatively the bound from the free test compound. Thecytokine receptor can be immobilized on various matrixes followed bywashing. Suitable matrices include plastic such as an ELISA plate,filters, and beads. Methods of immobilizing the receptor to a matrixinclude, without limitation, direct adhesion to plastic, use of acapture antibody, chemical coupling, and biotin avidin. The last step inthis approach involves the precipitation of antibody/antigen complex byany of several methods including those utilizing, e.g., an organicsolvent such as polyethylene glycol or a salt such as ammonium sulfate.Other suitable separation techniques include, without limitation, thefluorescein antibody magnetizable particle method described in Rattle,et al. (1984) Clin. Chem. 30(9):1457 1461, and the double antibodymagnetic particle separation as described in U.S. Pat. No. 4,659,678.

Methods for linking protein or fragments to various labels can involveactivated carboxyl groups either through the use of carbodiimide oractive esters to form peptide bonds, the formation of thioethers byreaction of a mercapto group with an activated halogen such aschloroacetyl, or an activated olefin such as maleimide, for linkage, orthe like. Fusion proteins will also find use in these applications.

Another diagnostic aspect of this invention involves use ofoligonucleotide or polynucleotide sequences taken from the sequence of acytokine receptor. These sequences can be used as probes for detectinglevels of the respective cytokine receptor in patients suspected ofhaving an immunological disorder. The preparation of both RNA and DNAnucleotide sequences, the labeling of the sequences, and the preferredsize of the sequences is well known in the art. Normally anoligonucleotide probe should have at least about 14 nucleotides, usuallyat least about 18 nucleotides, and the polynucleotide probes may be upto several kilobases. Various labels may be employed, most commonlyradionuclides, particularly ³²P. However, other techniques may also beemployed, such as using biotin modified nucleotides for introductioninto a polynucleotide. The biotin then serves as the site for binding toavidin or antibodies, which may be labeled with a wide variety oflabels, such as radionuclides, fluorescers, enzymes, or the like.Alternatively, antibodies may be employed which can recognize specificduplexes, including DNA duplexes, RNA duplexes, DNA RNA hybrid duplexes,or DNA protein duplexes. The antibodies in turn may be labeled and theassay carried out where the duplex is bound to a surface, so that uponthe formation of duplex on the surface, the presence of antibody boundto the duplex can be detected. The use of probes to the novel anti senseRNA may be carried out in conventional techniques such as nucleic acidhybridization, plus and minus screening, recombinational probing, hybridreleased translation (HRT), and hybrid arrested translation (HART). Thisalso includes amplification techniques such as polymerase chain reaction(PCR).

Diagnostic kits which also test for the qualitative or quantitativepresence of other markers are also contemplated. Diagnosis or prognosismay depend on the combination of multiple indications used as markers.Thus, kits may test for combinations of markers, see, e.g., Viallet, etal. (1989) Progress in Growth Factor Res. 1:89-97. Detection ofpolymorphic variations, which may reflect functional receptor signalingdifferences, may be useful in determining therapeutic strategy.Variations which reflect greater or lesser response to ligand may allowsubsetting of responsive/non-responsive patient pools.

The diagnostic method of the present invention provides a sample from atest subject, e.g., a patient suffering from an immune disorder, for usein measuring expression or activity of DCRS5 or p19. DCRS5 in bothnon-complexed forms and complexed forms, e.g., as DCRS5 complexed withIL-12beta1, can be measured. P19 in both non-complexed forms andcomplexed forms, e.g., as p19 complexed with p40, can be measured.Expression or activity can be compared with that from a control subjector control sample. A control sample can be, e.g., a sample ofnon-affected or non-inflammed tissue in the patient suffering from animmune disorder. Expression or activity from a control subject orcontrol sample can be provided as a predetermined value, e.g., acquiredfrom a statistically appropriate group of control subjects.

VIII. Therapeutic Utility

This invention provides reagents with significant therapeutic value,see, e.g., Levitzki (1996) Curr. Opin. Cell Biol. 8:239-244. Naturallyoccurring or recombinant cytokine receptors, fragments thereof, muteinreceptors, and antibodies, along with compounds identified as havingbinding affinity to the receptors or antibodies, should be useful in thetreatment of conditions exhibiting abnormal expression of the receptorsor their ligands. Such abnormality will typically be manifested byimmunological disorders, see, e.g., WO 01/18051. Additionally, thisinvention should provide therapeutic value in various diseases ordisorders associated with abnormal expression or abnormal triggering ofresponse to the ligand. For example, the p40/IL B30 ligand has beensuggested to be involved in development of cell mediated immunity, e.g.,anti-tumor activity, mounting of humoral and cellular immunity, andantiviral effects. In particular, the ligand appears to activate NK andT cells. Therapy may be combined with IL-18, IL-12, TNF, IFNγ,radiation/chemotherapy, adjuvants, or antitumor, antiviral, orantifungal compounds.

Conversely, antagonists, which may be combined with antagonists of TNF,IFNγ, IL-18, or IL-12, or with IL-10 or steroids, may be indicated inchronic Th1 mediated diseases, autoimmunity, or transplant and/orrejection situations, multiple sclerosis, psoriasis, chronicinflammatory conditions, rheumatoid arthritis, osteoarthritis, orinflammatory bowel diseases. Antagonists may take the form of antibodiesagainst the receptor subunits, soluble receptor constructs, antisensenucleic acids, or RNA interference nucleic acids, to one or more of thereceptor subunits. The matching of the p40/p19 ligand with receptorsubunits DCRS5 and IL-12R provides insight into indications for use ofthe agaonists and antagonists.

Therapeutically, based on the p40/p19 activities described, antagonistsof the cytokine may be effected, e.g., by soluble DCRS5, with or withoutsoluble IL-12Rβ1, or antibodies to either receptor subunit. Antagonistsmay be useful as inhibitors of undesirable immune or inflammatoryresponses, to target memory T cells, or in combination withIL-12/IL-112R antagonists, or other anti-inflammatories orimmunosuppressants. Clinical indications may be chronic inflammation ortransplant situations. Various polymorphisms may enhance or decreasereceptor function, and if dominant, might be useful as therapeutics.Identification of such variants may allow subsetting of responsive ornonresponsive patient pools. The reagents may be useful as detecting orlabeling reagents or ablative reagents for memory T cells and/or NKcells.

The invention contemplates methods of treatment using anti-sense nucleicacids or RNA interference nucleic acids to human p19 (SEQ ID NO:5) or tohuman DCRS5 (SEQ ID NO:1), see, e.g., Arenz and Schepers (2003)Naturwissenschaften 90:345-359; Sazani and Kole (2003) J. Clin. Invest.112:481-486; Pirollo, et al. (2003) Pharmacol. Therapeutics 99:55-77;Wang, et al. (2003) Antisense Nucl. Acid Drug Devel. 13:169-189;Haraoui, et al. (2000) Curr. Pharm. Biotechnol. 1:217-233; Alvarez, etal. (2001) Curr. Pharm. Des. 7:1059-1081; Sandborn and Targan (2002)Gastroenterol. 122:1592-1608.

Gene therapy may render desired cell populations response to p40/p19ligand, e.g., as adjuvants for tumor immunotherapy, to facilitateactivation of tumor infiltrating lymphocytes, T cells, or NK cells.Antisense or RNA interference strategies may be applied, e.g., toprevent receptor responsiveness.

Various abnormal conditions are known in cell types shown to produceboth IL-12 p40 and/or p19 mRNA by Northern blot analysis. See Berkow(ed.) The Merck Manual of Diagnosis and Therapy, Merck & Co., Rahway, N.J.; Thorn, et al. Harrison's Principles of Internal Medicine,McGraw-Hill, N.Y.; and Weatherall, et al. (eds.) Oxford Textbook ofMedicine, Oxford University Press, Oxford. Many other medical conditionsand diseases will be responsive to treatment by an agonist or antagonistprovided herein. See, e.g., Stites and Terr (eds.) (1991) Basic andClinical Immunology Appleton and Lange, Norwalk, Conn.; and Samter, etal. (eds.) Immunological Diseases Little, Brown and Co. Other likelyindications for treatment include bone remodeling, sexual dysfunction,prevention of neurodegenerative diseases, dementia, stress, and others.These problems should be susceptible to prevention or treatment usingcompositions provided herein.

Recombinant cytokine receptors, muteins, agonist or antagonistantibodies thereto, or antibodies can be purified and then administeredto a patient. These reagents can be combined for therapeutic use withadditional active ingredients, e.g., in conventional pharmaceuticallyacceptable carriers or diluents, along with physiologically innocuousstabilizers and excipients. These combinations can be sterile, e.g.,filtered, and placed into dosage forms as by lyophilization in dosagevials or storage in stabilized aqueous preparations. This invention alsocontemplates use of antibodies or binding fragments thereof which arenot complement binding.

Ligand screening using cytokine receptor or fragments thereof can beperformed to identify molecules having binding affinity to thereceptors. Subsequent biological assays can then be utilized todetermine if a putative ligand can provide competitive binding, whichcan block intrinsic stimulating activity. Receptor fragments can be usedas a blocker or antagonist in that it blocks the activity of ligand.Likewise, a compound having intrinsic stimulating activity can activatethe receptor and is thus an agonist in that it simulates the activity ofligand, e.g., inducing signaling. This invention further contemplatesthe therapeutic use of antibodies to cytokine receptors as antagonists.

The quantities of reagents necessary for effective therapy will dependupon many different factors, including means of administration, targetsite, reagent physiological life, pharmacological life, physiologicalstate of the patient, and other medicants administered. Thus, treatmentdosages should be titrated to optimize safety and efficacy. Typically,dosages used in vitro may provide useful guidance in the amounts usefulfor in situ administration of these reagents. Animal testing ofeffective doses for treatment of particular disorders will providefurther predictive indication of human dosage, see, e.g., Gilman, et al.(eds.) (1990) Goodman and Gilman's: The Pharmacological Bases ofTherapeutics, 8th Ed., Pergamon Press; and Remington's PharmaceuticalSciences, 17th ed. (1990), Mack Publishing Co., Easton, Pa. Methods foradministration are discussed therein and below, e.g., for oral,intravenous, intraperitoneal, or intramuscular administration,transdermal diffusion, and others. Pharmaceutically acceptable carrierswill include water, saline, buffers, and other compounds described,e.g., in the Merck Index, Merck & Co., Rahway, N.J. Because of thelikely high affinity binding, or turnover numbers, between a putativeligand and its receptors, low dosages of these reagents would beinitially expected to be effective. And the signaling pathway suggestsextremely low amounts of ligand may have effect. Thus, dosage rangeswould ordinarily be expected to be in amounts lower than 1 mMconcentrations, typically less than about 10 μM concentrations, usuallyless than about 100 nM, preferably less than about 10 μM (picomolar),and most preferably less than about 1 fM (femtomolar), with anappropriate carrier. Slow release formulations, or slow releaseapparatus will often be utilized for continuous administration.

Cytokine receptors, fragments thereof, and antibodies or its fragments,antagonists, and agonists, may be administered directly to the host tobe treated or, depending on the size of the compounds, it may bedesirable to conjugate them to carrier proteins such as ovalbumin orserum albumin prior to their administration. Therapeutic formulationsmay be administered in many conventional dosage formulations. While itis possible for the active ingredient to be administered alone, it ispreferable to present it as a pharmaceutical formulation. Formulationscomprise at least one active ingredient, as defined above, together withone or more acceptable carriers thereof. Each carrier must be bothpharmaceutically and physiologically acceptable in the sense of beingcompatible with the other ingredients and not injurious to the patient.Formulations include those suitable for oral, rectal, nasal, orparenteral (including subcutaneous, intramuscular, intravenous andintradermal) administration. The formulations may conveniently bepresented in unit dosage form and may be prepared by methods well knownin the art of pharmacy. See, e.g., Gilman, et al. (eds.) (1990) Goodmanand Gilman's: The Pharmacological Bases of Therapeutics, 8th Ed.,Pergamon Press; and Remington's Pharmaceutical Sciences, 17th ed.(1990), Mack Publishing Co., Easton, Pa.; Avis, et al. (eds.) (1993)Pharmaceutical Dosage Forms: Parenteral Medications Dekker, NY;Lieberman, et al. (eds.) (1990) Pharmaceutical Dosage Forms: TabletsDekker, NY; and Lieberman, et al. (eds.) (1990) Pharmaceutical DosageForms: Disperse Systems Dekker, NY. The therapy of this invention may becombined with or used in association with other therapeutic agents,particularly agonists or antagonists of other cytokine receptor familymembers.

The invention provides reagents and methods for the treatment anddiagnosis of asthma or allergies. These disorders are associated withincreased expression or activity of IL-6, IL-19, CXCL1 (a.k.a.GROalpha), IL-17, and GM-CSF, see, e.g., Cembrzynska-Nowak, et al.(1998) Arch. Immunol. Ther. Exp. (Warsz) 46:381-386; Hsieh, et al.(1996) J. Allergy Clin. Immunol. 98:580-587; Prause, et al. (2003) Eur.J. Pharmacol. 462:193-198. Molet, et al. (2001) J. Allergy Clin.Immunol. 108:430-438. Linden (2001) Int. Arch. Allergy Immunol.126:179-184; Cates, et al. (2003) J. Allergy Clin Immunol. 111:1076-1086; Yamashita, et al. (2002) Cell Immunol. 219:92-97. Alsoprovided are reagents and methods for COPD, a disorder connected withincreased expression or activity of IL-6, CXCL1, and GM-CSF, see, e.g.,Chung, et al. (2001) Eur. Respir. J. Suppl. 34:50s-59s; Traves, et al.(2002) Thorax 57:590-595; Profita, et al. (2003) Thorax 58:573-579.

The invention also provides reagents and methods for rheumatoidarthritis, a disorder involving increased expression or activity ofIL-6, CXCL1, IL-17, and GM-CSF, see, e.g., Gentiletti and Fava (2003)Arthritis Rheum. 48:1471-1474; Nakahara, et al. (2003) Arthritis Rheum.48:1521-1529; Konig, et al. (2000) Virchows Arch. 436:449-458; Koch, etal. (1995) J. Immunol. 155:3660-3666; Borzi, et al. (1999) FEBS Lett.455:238-242; Boiardi, et al. (1999) Clin. Exp. Rheumatol. 17:419-425;Hogan, et al. (1994) Cytokine 6:61-69; Kehlen, et al. (2002) Clin. Exp.Immunol. 127:539-546; Cook, et al. (2001) Arthritis Res. 3:293-298.

Also provided are reagents and methods for the treatment and diagnosisof inflammatory bowel disorder (IBD), a disorder characterized byincreased expression or activity of IL-6, CXCL-1, IL-17, and GM-CSF,see, e.g., Rahbar, et al. (2003) Inflamm. Bowel Dis. 9:154-161; Isaacs,et al. (1992) Gastroenterol. 103:1587-1595; Imada, et al. (2001) Scand.J. Gastroenterol. 36:854-864; Brandt, et al. (1998) Eur. Cytokine Netw.9:647-653; Fujino, et al. (2003) Gut 52:65-70; Nielsen, et al. (2003)Scand. J. Gastroenterol. 38:180-185; Carlson, et al. (2002) Gut50:501-506. Additionally encompassed are reagents and methods for thediagnosis and treatment of inflammatory disorders of the skin, e.g.,psoriasis, a family of disorders associated with increased expression oractivity of IL-6, CXCL1, IL-17, and GM-CSF, see, e.g., Ishihara andHirano (2002) Cytokine Growth Factor Rev. 13:357-368; Gillitzer, et al.(1996) J. Invest. Dermatol. 107:778-782; Steude, et al. (2002) J.Invest. Dermatol. 119:1254-1260; Albanesi, et al. (2000) J. Invest.Dermatol. 115:81-87; Schon, et al. (2000) J. Invest. Dermatol.114:976-983.

IX. Screening

Drug screening using DCRS5 or fragments thereof can be performed toidentify compounds having binding affinity to the receptor subunit,including isolation of associated components. Subsequent biologicalassays can then be utilized to determine if the compound has intrinsicstimulating activity and is therefore a blocker or antagonist in that itblocks the activity of the ligand.

Moreover, matching of the p40/p19 ligand with the functional receptor ofDCRS3 with IL-12Rβ1, allows screening for antagonists and agonists witha positive signaling control. Small molecule or antibody screening canbe done.

One method of drug screening utilizes eukaryotic or prokaryotic hostcells which are stably transformed with recombinant DNA moleculesexpressing the DCRS5 in combination with another cytokine receptorsubunit, e.g., IL-12Rβ1. The signaling is believed to use STAT4. Cellsmay be isolated which express a receptor in isolation from otherfunctional receptors. Such cells, either in viable or fixed form, can beused for standard antibody/antigen or ligand/receptor binding assays,see, e.g., Parce, et al. (1989) Science 246:243-247, and Owicki, et al.(1990) Proc. Natl. Acad. Sci. USA 87:4007-4011, which describe sensitivemethods to detect cellular responses. Competitive assays areparticularly useful, where the cells are contacted and incubated with alabeled receptor or antibody having known binding affinity to theligand, such as ¹²⁵I-antibody, and a test sample whose binding affinityto the binding composition is being measured. The bound and free labeledbinding compositions are then separated to assess the degree of ligandbinding. The amount of test compound bound is inversely proportional tothe amount of labeled receptor binding to the known source. Manytechniques can be used to separate bound from free ligand to assess thedegree of ligand binding. This separation step could typically involve aprocedure such as adhesion to filters followed by washing, adhesion toplastic followed by washing, or centrifugation of the cell membranes.Viable cells could also be used to screen for the effects of drugs oncytokine mediated functions, e.g., STAT4 signaling and others. Somedetection methods allow for elimination of a separation step, e.g., aproximity sensitive detection system.

The broad scope of this invention is best understood with reference tothe following examples, which are not intended to limit the inventionsto the specific embodiments.

EXAMPLES I. General Methods

Some of the standard methods are described or referenced, e.g., inManiatis, et al. (1982) Molecular Cloning, A Laboratory Manual ColdSpring Harbor Laboratory, Cold Spring Harbor Press; Sambrook, et al.(1989) Molecular Cloning: A Laboratory Manual, (2d ed.), vols. 1-3, CSHPress, NY; or Ausubel, et al. (1987 and Supplements) Current Protocolsin Molecular Biology, Greene/Wiley, New York. Methods for proteinpurification include such methods as ammonium sulfate precipitation,column chromatography, electrophoresis, centrifugation, crystallization,and others. See, e.g., Ausubel, et al. (1987 and periodic supplements);Coligan, et al. (eds.) (1996 and periodic supplements) Current ProtocolsIn Protein Science Greene/Wiley, New York; Deutscher (1990) “Guide toProtein Purification” in Methods in Enzymology, vol. 182, and othervolumes in this series; and manufacturer's literature on use of proteinpurification products, e.g., Pharmacia, Piscataway, N.J., or Bio-Rad,Richmond, Calif. Combination with recombinant techniques allow fusion toappropriate segments, e.g., to a FLAG sequence or an equivalent whichcan be fused via a protease-removable sequence. See, e.g., Hochuli(1990) “Purification of Recombinant Proteins with Metal ChelateAbsorbent” in Setlow (ed.) Genetic Engineering, Principle and Methods12:87-98, Plenum Press, N.Y.; and Crowe, et al. (1992) QIAexpress: TheHigh Level Expression & Protein Purification System QIAGEN, Inc.,Chatsworth, Calif.

Computer sequence analysis is performed, e.g., using available softwareprograms, including those from the GCG (U. Wisconsin) and GenBanksources. Public sequence databases were also used, e.g., from GenBankand others.

Many techniques applicable to IL-10 receptors may be applied to theDCRS5, as described, e.g., in U.S. Ser. No. 08/110,683 (IL-10 receptor).

II. Functional Cloning

It was observed that anti-hIL-12Rβ1 antibody blocked responses of humanT cells to p40/p19, and the p40/p19 bound to IL-12Rβ1. This suggestedthat IL-12Rβ1 was one subunit of the receptor complex for p40/p19.

A mouse T cell population was identified which responded to p40/p19 butnot to IL-12, and another population which responded to IL-12 but notp40/p19. In addition, it was observed that Ba/F3 cells expressingrecombinant mIL-12Rβ1 and mIL-12Rβ2 responded to IL-12, but not top40/p19. These results collectively indicated that the receptor complexfor p40/p19 contained the IL-12Rβ1 and at least one other subunit whichwas not IL-12Rβ2. Accordingly an expression cloning strategy was devisedto isolate this second receptor component.

A cDNA library was prepared from mRNA isolated from Kit225 cells, anIL-2-dependent human T cell line which responds to both IL-12 andp40/p19. The cDNA library was made using a retroviral expression vector,pMX. Ba/F3 cells expressing recombinant hIL-12Rβ1 were infected withthis cDNA library, allowed to recover for 3-4 days in IL-3, then washedand plated at ˜15,000 cells/well in 96 well plates in medium containing50 ng/ml hyper-hp40/hp19. See, WO 01/18051. Cultures were supplementedevery 5 days with additional hyper-hp40/hp19. After approximately twoweeks 5-10% of the wells exhibited cell growth. Cells were recoveredfrom each well, expanded individually in larger cultures inhyper-hp40/p19, and tested for growth dependence on hyper-hp40/hp19.

Cells which were p40/p19-dependent for growth were analyzed by PCR forretroviral cDNA inserts. Out of more than 40 isolates analyzed, all butone contained cDNAs encoding the novel receptor DCRS5. This candidatehuman cDNA was cloned in an expression vector and transfected into Ba/F3cells expressing hIL-12Rβ1. These cells became responsive to p40/p19;thus, we concluded that the novel cDNA encoded the desired DCRS5,functionally an p19 receptor subunit.

III. Features of Full-Length DCRS5; Chromosomal Location

The cytoplasmic domain of DCRS5 is not overall closely related to othercytokine receptor cytoplasmic domains, a common observation in thisfamily of molecules. The cytoplasmic domain contains seven tyr residues,at least three of which are part of recognizable SH2-binding motifs:YEDI, YKPQ, and YFPQ. The YEDI motif is similar to identified bindingsites for the tyrosine phosphatase shp2. The latter two motifs are verysimilar to sequences known to bind Stat1/Stat3, or Stat3, respectively.The YKPQ motif, together with nearby flanking sequences, also resemblesto a degree the motifs in Stat4 and IL-12Rβ2 which are known to bindStat1-3. This is consistent with preliminary data suggesting thatp40/p19, like IL-12, activates Stat4.

PCR primers derived from the DCRS5 sequence are used to probe a humancDNA library. Sequences may be derived, e.g., from SEQ ID NO:1,preferably those adjacent the ends of sequences. Full length cDNAs forprimate, rodent, or other species DCRS5 are cloned, e.g., by DNAhybridization screening of λgt10 phage. PCR reactions are conductedusing T. aquaticus Taqplus® DNA polymerase (Stratagene, La Jolla,Calif.) under appropriate conditions.

Chromosome spreads are prepared. In situ hybridization is performed onchromosome preparations obtained from phytohemagglutinin-stimulatedhuman lymphocytes cultured for 72 h. 5-bromodeoxyuridine was added forthe final seven hours of culture (60 μg/ml of medium) to ensure aposthybridization chromosomal banding of good quality.

A PCR fragment, amplified with the help of primers, is cloned into anappropriate vector. The vector is labeled by nick-translation with ³H.The radiolabeled probe is hybridized to metaphase spreads at finalconcentration of 200 ng/ml of hybridization solution (Mattei, et al.(1985) Hum. Genet. 69:327-331).

After coating with nuclear track emulsion (KODAK NTB2), slides areexposed. To avoid any slipping of silver grains during the bandingprocedure, chromosome spreads are first stained with buffered Giemsasolution and metaphase photographed. R-banding is then performed by thefluorochrome-photolysis-Giemsa (FPG) method and metaphasesrephotographed before analysis.

Similar appropriate methods are used for other species.

IV. Localization of DCRS5 mRNA

Human multiple tissues (cat. no. 1, 2) and cancer cell line blots (cat.no. 7757-1), containing approximately 2 μg of polyA⁺ RNA per lane arefrom Clontech (Palo Alto, Calif.). Probes are radiolabeled with[α-³²P]dATP, e.g., using the Amersham Rediprime® random primer labellingkit (RPN 1633). Prehybridization and hybridizations are performed, e.g.,at 65° C. in 0.5 M Na₂HPO₄, 7% SDS, 0.5 M EDTA (pH 8.0). High stringencywashes are conducted, e.g., at 65° C. with two initial washes in 2×SSC,0.1% SDS for 40 min followed by a subsequent wash in 0.1×SSC, 0.1% SDSfor 20 min. Membranes are then exposed at −70° C. to X-ray film (Kodak)in the presence of intensifying screens. More detailed studies by cDNAlibrary Southerns are performed with selected appropriate human DCRS5clones to examine their expression in hemopoietic or other cell subsets.

Alternatively, two appropriate primers are selected from SEQ ID NO:1.RT-PCR is used on an appropriate mRNA sample selected for the presenceof message to produce a cDNA, e.g., a sample which expresses the gene.

Full length clones may be isolated by hybridization of cDNA librariesfrom appropriate tissues pre-selected by PCR signal. Northern blots canbe performed.

Message for genes encoding DCRS5 will be assayed by appropriatetechnology, e.g., PCR, immunoassay, hybridization, or otherwise. Tissueand organ cDNA preparations are available, e.g., from Clontech, MountainView, Calif. Identification of sources of natural expression are useful,as described. And the identification of the functional receptor subunitpairing allows for prediction of what cells express the combination ofreceptor subunits which will result in a physiological responsiveness toeach of the cytokine ligands.

For mouse distribution, e.g., Southern Analysis can be performed: DNA (5μg) from a primary amplified cDNA library was digested with appropriaterestriction enzymes to release the inserts, run on a 1% agarose gel, andtransferred to a nylon membrane (Schleicher and Schuell, Keene, N.Y.).

Samples for mouse mRNA isolation may include: resting mouse fibroblasticL cell line (C200); Braf:ER (Braf fusion to estrogen receptor)transfected cells, control (C201); T cells, TH1 polarized (Mel14 bright,CD4⁺ cells from spleen, polarized for 7 days with IFN-γ and anti-IL-4;T200); T cells TH2 polarized (Mel14 bright, CD4⁺ cells from spleen,polarized for 7 days with IL-4 and anti-IFN-γ; T201); T cells highly Th1polarized (see Openshaw, et al. (1995) J. Exp. Med. 182:1357-1367;activated with anti-CD3 for 2, 6, 16 h pooled; T202); T cells highly TH2polarized (see Openshaw, et al., supra; activated with anti-CD3 for 2,6, 16 h pooled; T203); CD44⁻ CD25⁺ pre T cells, sorted from thymus(T204); TH1 T cell clone D1.1, resting for 3 weeks after laststimulation with antigen (T205); TH1 T cell clone D1.1, 10 μg/ml ConAstimulated 15 h (T206); TH2 T cell clone CDC35, resting for 3 weeksafter last stimulation with antigen (T207); TH2 T cell clone CDC35, 10microgram/ml ConA stimulated 15 h (T208); Mel14⁺ naïve T cells fromspleen, resting (T209); Mel14⁺ T cells, polarized to Th1 withIFN-γ/IL-12/anti-IL-4 for 6, 12, 24 h pooled (T210); Mel14⁺ T cellspolarized to Th2 with IL-4/anti-IFN-γ for 6, 13, 24 h pooled (T211);unstimulated mature B cell leukemia cell line A20 (B200); unstimulated Bcell line CH12 (B201); unstimulated large B cells from spleen (B202); Bcells from total spleen, LPS activated (B203); metrizamide enricheddendritic cells from spleen, resting (D200); dendritic cells from bonemarrow, resting (D201); monocyte cell line RAW 264.7 activated with LPS4 h (M200); bone-marrow macrophages derived with GM and M-CSF (M201);macrophage cell line J774, resting (M202); macrophage cell lineJ774+LPS+anti-IL-10 at 0.5, 1, 3, 6, 12 h pooled (M203); macrophage cellline J774+LPS+IL-10 at 0.5, 1, 3, 5, 12 h pooled (M204); aerosolchallenged mouse lung tissue, Th2 primers, aerosol OVA challenge 7, 14,23 h pooled (see Garlisi, et al. (1995) Clinical Immunology andimmunopathology 75:75-83; X206); Nippostrongulus-infected lung tissue(see Coffman, et al. (1989) Science 245:308-310; X200); total adultlung, normal (O200); total lung, rag-I (see Schwarz, et al. (1993)Immunodeficiency 4:249-252; 0205); IL-10 K. O. spleen (see Kuhn, et al.(1991) Cell 75:263-274; X201); total adult spleen, normal (0201); totalspleen, rag-1 (O207); IL-10 K. O. Peyer's patches (O202); total Peyer'spatches, normal (O210); IL-10 K.O. mesenteric lymph nodes (X203); totalmesenteric lymph nodes, normal (O211); IL-10 K.O. colon (X203); totalcolon, normal (O212); NOD mouse pancreas (see Makino, et al. (1980)Jikken Dobutsu 29:1-13; X205); total thymus, rag-1 (O208); total kidney,rag-1 (O209); total heart, rag-1 (O202); total brain, rag-1 (O203);total testes, rag-1 (O204); total liver, rag-1 (O206); rat normal jointtissue (O300); and rat arthritic joint tissue (X300).

Samples for human mRNA isolation may include: peripheral bloodmononuclear cells (monocytes, T cells, NK cells, granulocytes, B cells),resting (T100); peripheral blood mononuclear cells, activated withanti-CD3 for 2, 6, 12 h pooled (T101); T cell, TH0 clone Mot 72, resting(T102); T cell, TH0 clone Mot 72, activated with anti-CD28 and anti-CD3for 3, 6, 12 h pooled (T103); T cell, TH0 clone Mot 72, anergic treatedwith specific peptide for 2, 7, 12 h pooled (T104); T cell, TH1 cloneHY06, resting (T107); T cell, TH1 clone HY06, activated with anti-CD28and anti-CD3 for 3, 6, 12 h pooled (T108); T cell, TH1 clone HY06,anergic treated with specific peptide for 2, 6, 12 h pooled (T109); Tcell, TH2 clone HY935, resting (T110); T cell, TH2 clone HY935,activated with anti-CD28 and anti-CD3 for 2, 7, 12 h pooled (T111); Tcells CD4⁺ CD45RO⁻ T cells polarized 27 days in anti-CD28, IL-4, andanti IFN-γ, TH2 polarized, activated with anti-CD3 and anti-CD28 4 h(T116); T cell tumor lines Jurkat and Hut78, resting (T117); T cellclones, pooled AD130.2; Tc783.12, Tc783.13, Tc783.58, Tc782.69, resting(T118); T cell random γδ T cell clones, resting (T119); splenocytes,resting (B100); splenocytes, activated with anti-CD40 and IL-4 (B101); Bcell EBV lines pooled WT49, RSB, JY, CVIR, 721.221, RM3, HSY, resting(B102); B cell line JY, activated with PMA and ionomycin for 1, 6 hpooled (B103); NK 20 clones pooled, resting (K100); NK 20 clones pooled,activated with PMA and ionomycin for 6 h (K101); NKL clone, derived fromperipheral blood of LGL leukemia patient, IL-2 treated (K106); NKcytotoxic clone 640-A30-1, resting (K107); hematopoietic precursor lineTF1, activated with PMA and ionomycin for 1.6 h pooled (C100); U937premonocytic line, resting M100); U937 premonocytic line, activated withPMA and ionomycin for 1, 6 h pooled (M101); elutriated monocytes,activated with LPS, IFNγ, anti-IL-10 for 1, 2, 6, 12, 24 h pooled(M102); elutriated monocytes, activated with LPS, IFNγ, IL-10 for 1, 2,6, 12, 24 h pooled (M103); elutriated moncytes, activated with LPS,IFNγ, anti-IL-10 for 4, 16 h pooled (M106); elutriated monocytes,activated with LPS, IFNγ, IL-10 for 4, 16 h pooled (M107); elutriatedmonocytes, activated LPS for 1 h (M108); elutriated monocytes, activatedLPS for 6 h (M109); DC 70% CD1a⁺, from CD34⁺ GM-CSF, TNFα12 days,resting (D101); DC 70% CD1a⁺, from CD34⁺ GM-CSF, TNFα12 days, activatedwith PMA and ionomycin for 1 hr (D102); DC 70% CD1a⁺, from CD34⁺ GM-CSF,TNFα12 days, activated with PMA and ionomycin for 6 hr (D103); DC95%CD1a⁺, from CD34⁺, GM-CSF, TNFα12 days FACS sorted, activated with PMAand ionomycin for 1, 6 hr pooled (D104); DC 95% CD14⁺, ex CD34⁺ GM-CSF,TNFα12 days FACS sorted, activated with PMA and ionomycin 1, 6 hr pooled(D105); DC CD1a⁺ CD86⁺, from CD34⁺ GM-CSF; TNFα12 days sorted, activatedwith PMA and ionmycin for 1.6 h pooled (K106); DC from monocytes GM-CSF,IL-4 5 days, resting (D107); DC from monocytes GM-CSF, IL-4 5 days,resting (D108); DC from monocytes GM-CSF, IL-4 5 days, activated LPS 4,16 h pooled (D109); DC from monocytes GM-CSF, IL-4 5 days, activatedTNFα, monocyte supe for 4, 16 h pooled (D110); leiomyoma L11 benigntumor (X101); normal myometrium M5 (O115); malignant leiomyosarcoma GS1(X103); lung fibroblast sarcoma line MRC5, activated with PMA andionomycin for 1, 6 h pooled (C101); kidney epithelial carcinoma cellline CHA, activated with PMA and ionomycin for 1, 6 h pooled (C102);kidney fetal 28 wk male (O100); lung fetal 28 wk male (O101); liverfetal 28 wk male (O102); heart fetal 28 wk male (O103); brain fetal 28wk male (O104); gallbladder fetal 28 wk male (O106); small intestinefetal 28 wk male (O107); adipose tissue fetal 28 wk male (O108); ovaryfetal 25 wk female (O109); uterus fetal 25 wk female (O110); testesfetal 28 wk male (O111); spleen fetal 28 wk male (O112); adult placenta28 wk (O113); and tonsil inflamed, from 12 year old (X100).

Similar samples may isolated in other species for evaluation.

V. Cloning of species counterparts of DCRS5

Various strategies are used to obtain species counterparts of the DCRS5,preferably from other primates or rodents. One method is by crosshybridization using closely related species DNA probes. It may be usefulto go into evolutionarily similar species as intermediate steps. Anothermethod is by using specific PCR primers based on the identification ofblocks of similarity or difference between genes, e.g., areas of highlyconserved or nonconserved polypeptide or nucleotide sequence.

Database searches may identify similar sequences and allow production ofappropriate probes.

VI. Production of Mammalian DCRS5 Protein

An appropriate, e.g., glutathione S-transferase (GST), fusion constructis engineered for expression, e.g., in E. coli. For example, a mouseIGIF pGEX® plasmid is constructed and transformed into E. coli. Freshlytransformed cells are grown, e.g., in LB medium containing 50 μg/mlampicillin and induced with IPTG (Sigma, St. Louis, Mo.). Afterovernight induction, the bacteria are harvested and the pelletscontaining the DCRS5 protein are isolated. The pellets are homogenized,e.g., in TE buffer (50 mM Tris-base pH 8.0, 10 mM EDTA and 2 mMPefabloc®) in 2 liters. This material is passed through a microfluidizer(Microfluidics, Newton, Mass.) three times. The fluidized supernatant isspun down on a Sorvall GS-3 rotor for 1 h at 13,000 rpm. The resultingsupernatant containing the cytokine receptor protein is filtered andpassed over a glutathione-Sepharose® column equilibrated in 50 mMTris-base pH 8.0. The fractions containing the DCRS5-GST fusion proteinare pooled and cleaved, e.g., with thrombin (Enzyme ResearchLaboratories, Inc., South Bend, Ind.). The cleaved pool is then passedover a Q-Sepharose® column equilibrated in 50 mM Tris-base. Fractionscontaining DCRS5 are pooled and diluted in cold distilled water, tolower the conductivity, and passed back over a fresh Q-Sepharose®column, alone or in succession with an immunoaffinity antibody column.Fractions containing the DCRS5 protein are pooled, aliquoted, and storedin the −70° freezer.

Comparison of the circular dichroism spectrum with cytokine receptorprotein may suggest that the protein is correctly folded, see, e.g.,Hazuda, et al. (1969) J. Biol. Chem. 264:1689-1693.

VII. Preparation of Antibodies Specific for DCRS5

Inbred Balb/c mice are immunized intraperitoneally with recombinantforms of the protein, e.g., purified DCRS5 or stable transfected NIH-3T3cells. Animals are boosted at appropriate time points with protein, withor without additional adjuvant, to further stimulate antibodyproduction. Serum is collected, or hybridomas produced with harvestedspleens.

Alternatively, Balb/c mice are immunized with cells transformed with thegene or fragments thereof, either endogenous or exogenous cells, or withisolated membranes enriched for expression of the antigen. Serum iscollected at the appropriate time, typically after numerous furtheradministrations. Various gene therapy techniques may be useful, e.g., inproducing protein in situ, for generating an immune response. Serum orantibody preparations may be cross-absorbed or immunoselected to preparesubstantially purified antibodies of defined specificity and highaffinity.

Monoclonal antibodies may be made. For example, splenocytes are fusedwith an appropriate fusion partner and hybridomas are selected in growthmedium by standard procedures. Hybridoma supernatants are screened forthe presence of antibodies which bind to the DCRS5, e.g., by ELISA orother assay. Antibodies which specifically recognize specific DCRS5embodiments may also be selected or prepared.

In another method, synthetic peptides or purified protein are presentedto an immune system to generate monoclonal or polyclonal antibodies.See, e.g., Coligan (ed.) (1991) Current Protocols in ImmunologyWiley/Greene; and Harlow and Lane, supra. In appropriate situations, thebinding reagent is either labeled as described above, e.g., fluorescenceor otherwise, or immobilized to a substrate for panning methods. Nucleicacids may also be introduced into cells in an animal to produce theantigen, which serves to elicit an immune response. See, e.g., Wang, etal. (1993) Proc. Natl. Acad. Sci. USA 90:4156-4160; Barry, et al. (1994)BioTechniques 16:616-619; and Xiang, et al. (1995) Immunity 2:129-135.

VIII. Production of Fusion Proteins with DCRS5

Various fusion constructs are made with DCRS5, including embodimentscombining such with IL-12Rβ1 sequence. A portion of the appropriate geneis fused to an epitope tag, e.g., a FLAG tag, or to a two hybrid systemconstruct, see, e.g., Fields and Song (1989) Nature 340:245-246. Theepitope tag may be used in an expression cloning procedure withdetection with anti-FLAG antibodies to detect a binding partner, e.g.,ligand for the respective cytokine receptor. The two hybrid system mayalso be used to isolate proteins which specifically bind to DCRS5.

IX Structure Activity Relationship

Information on the criticality of particular residues is determinedusing standard procedures and analysis. Standard mutagenesis analysis isperformed, e.g., by generating many different variants at determinedpositions, e.g., at the positions identified above, and evaluatingbiological activities of the variants. This may be performed to theextent of determining positions which modify activity, or to focus onspecific positions to determine the residues which can be substituted toeither retain, block, or modulate biological activity.

Alternatively, analysis of natural variants can indicate what positionstolerate natural mutations. This may result from populational analysisof variation among individuals, or across strains or species. Samplesfrom selected individuals are analyzed, e.g., by PCR analysis andsequencing. This allows evaluation of population polymorphisms.

X. Coexpression of DCRS5 and IL-12Rβ1

A vector, or vectors, encoding the respective gene may be transfectedinto a cell. Preferably, such vector will have selection markers toidentify which cells have successfully been transformed. Coexpression ofthe two genes will allow the gene products to properly associate to formactive receptor complexes. Alternatively, use of methods causingassociation of functional dimers are available, see, e.g., O'Shea, etal. (1989) Science 245:646-648; Kostelny, et al. (1992) J. Immunol.148:1547-1553; Patel, et al. (1996) J. Biol. Chem. 271:30386-30391.Expression of extracellular domains, and physical association, e.g.,driven by Fos/Jun leucine zipper affinity, will result in ligand bindingconstructs which should act as binding compounds for diagnostic ortherapeutic uses.

XI. Distribution of p19 (a.k.a. IL-B30), p40, and DCRS5 (a.k.a. IL-23R)

P19, p40, and DCRS5, are expressed by various cells and tissues, asdetermined by Taqman® real time PCR assays (PE Applied Biosystems,Foster City, Calif.), where the results are relative to ubiquitinexpression (Table 2). Ubiquitin expression is set to one. Expression ofboth p19 and p40 were found to be elevated in inflammatory skinconditions, e.g., psoriasis and atopic dermatitis, and in response toAscaris challenge (Table 2). Expression of p19 was elevated inhypersensitivity pneumonitis, idiopathic pulmonary fibrosis, and ininflammatory bowel disorder (IBD), e.g., Crohn's disease (Table 2).IL-23R (a.k.a. DCRS5) expression was found to increase, e.g., inpsoriasis and rheumatoid arthritis (Table 2).

TABLE 2 Expression of p19, p40, and IL-23R by cells and tissues byTaqman ® analysis. Expression of p19 (relative to ubiqutin (1.0)) Humanskin, normal 13.7 Human skin, psoriasis 30.3 Human skin, atopicdermatitis 16.1 Human lung control 52 Human hypersensitivity pneumonitis104 Human lung idiopathic pulmonary fibrosis 96 Monkey lung control 50Monkey Ascaris 4 hours 430 Human epithelial cell, small airway 43 Humanepithelial cell, small airway, activated IL-4, IL-13, 158 TNFalpha Coloncontrol 0.8 Colon Crohn's 29-73 Human synovia control 3.1 Human synoviarheumatoid arthritis 4.7 Mast cell resting 22 Mast cell, activatedcrosslink IgE receptor 500 T cell resting 55 T cell activated 294 NKcell resting 44 NK cell activated PMA/ionomycin 6 hours 851 Expressionof p40 (relative to ubiquitin (1.0)) Human skin, normal 4.7 Human skin,psoriasis 19.4 Human skin, atopic dermatitis 8.3 Monkey lung control 0.2Monkey lung, 4 hour Ascaris 4.7 Human dendritic cells, resting 0.0 Humandendritic cells, activated TNFalpha, TGFbeta 4391 Human dendritic cells,activated lipopolysaccharide (LPS) 255 Expression of human IL-23R(a.k.a. DCRS5) (relative to ubiquitin (1.0)) Human skin, normal 4.2Human skin, psoriasis 8.9 Human skin, atopic dermatitis 5.9 Humansynovia control 0.28 Human synovia rheumatoid arthritis 1.40

XII. Histology of IL-23 receptor (IL-23R)

Human tissues were subjected to histological analysis using anti-IL-23Rantibody (24F9) and an isotype control antibody (3F11) (Table 3). Asubset of lymphocytes, macrophages, and rare plasma cells, showedpositive staining by the anti-IL-23R antibody. The positively staininglymphocytes were located in interfollicular areas rather than ingerminal centers of the lymph node.

Synovial samples from rheumatoid arthritis (RA) demonstrated staining ofinflammatory cells, particularly plasma cells, that was more intense andmore prevalent of inflammatory cells, than samples from normal controls.Normal synovial samples do not contain infiltrates of inflammatorycells.

Samples from colon and small intestines with inflammatory bowel disorder(IBD), i.e., Crohn's disease and ulcerative colitis, revealed a greaterprevalence of positive-testing lymphocytes and plasma cells, than innormal controls. The increase in prevalence was increased in proportionto the increase in overall numbers of the inflammatory cells in thetissues. Lung samples from chronic obstructive pulmonary disorder (COPD)showed positive-testing Clara cells, while Clara cells from a normalpatient sample was negative. Skin sample testing from a normal 62 yearold male showed a lymphocyte staining value of 0, while a psoriatic skinsample from a 54 year old showed a lymphocyte value of 2 (rare).

TABLE 3 Histology of human tissues. Staining with anti-IL-23R antibody(24F9) relative to isotype control antibody. The number reflectsintensity of staining (—) means not determined. Epithelial Lympho-Macro- Plasma Clara cell or Endo- Source of tissue. cyte phage cell cellepithelium thelium Normal colon, 35 year 2 (rare) 2 (occasional) 2(rare) — 0 0 old female. Colon ulcerative colitis, 4 (occasional) 4(rare) 0 — 0 — 62 year old female. Colon ulcerative colitis, 4 (rare) 3(rare) 2 (rare) — 0 — 33 year old male. Colon ulcerative colitis, 4(occasional) 4 (rare) 2 (rare) — 0 — 44 year old male. Small intestines,2 (rare) 4 2 (rare) — — — normal, 75 year old male. Small intestines, 3(rare) 3 (occasional) 0 (most — — 0 Crohn's, 22 year male. Smallintestine, 4 (occasional) 4 (occasional) 2 (occasional) — — — Crohn'sunknown #1. Small intestines; 4 (rare) 3 (occasional) 2 (rare) — — —Crohn's unknown #2. Normal lung, 73 year old female. 0 0 — 0 0 0 Lung,COPD, 59 year 3 old male, 3 (rare) 0 2 (rare) 2 (occasional) 0 — LungCOPD, 68 year old female. 3 (rare) 0 0 2 (occasional) 0 — Lung COPD, 75year old male. 3 (rare) 1 0 — 0 — Synovium rheumatoid 3 (rare) 3 (rare)3 (rare) — arthritis, 66 year old female. Synovium rheumatoid 4 (rare) 3(rare) 2 (rare) — arthritis, 40 year old male. Synovium rheumatoid 4(rare) 4 (rare) 3 (occasional) — arthritis, 37 year old male.

XIII. Administration of IL-23 hyperkine to Mice and Gene Expression

C57BI6/NT mice were treated with murine IL-23 hyperkine or saline,followed by determination of expression of 157 genes by Taqman® realtime PCR analysis. Each mouse was injected intradermally, in the back,with either saline or with 10 micrograms IL-23 hyperkine. Tissue sampleswere taken and extracted at either 1, 3, or 7 days after injection,where the samples from the three dates were pooled, and then used forTaqman® analysis. The ratio of gene expression with and without IL-23hyperkine treatment is shown (Table 4). IL-23 hyperkine provoked anincrease in expression of 2-fold, or greater, for 15 of the 157 genestested (Table 4). IL-6, CXCL-1, IL-17, and GM-CSF, which increased withIL-23 treatment, are cytokines that show increased expression oractivity in asthma or allergies, COPD, rheumatoid arthritis, IBD, andpsoriasis (Table 4).

TABLE 4 Ratio of [Gene expression with IL-23]/[Gene expression withsaline] IL-6 33 IL-19 32 CXCL-1 (GRO-alpha) 11 IL-17 9 mMUC-5ac.fcgi 8secretory leukoprotease inhibitor (SLPI) 5 granulocyte macrophage-colonystimulating factor 5 (GM-CSF) TNFSF5 (CD40L) 3 MAdCAM-1 3interferon-gamma (IFN-gamma) 3 IL-9 3 12-lipoxygenase 2 tissue inhibitorof metalloproteinases-1 (TIMP-1) 2 IL-1alpha 2 IL-17RC 2

XIV. IL-23 Modulates Collagen-Induced Arthritis (CIA)

P19 knockout (p19KO) mice were prepared (Cua, et al. (2003) Nature421:744-748). The p19KO mice were deficient in IL-23, a heterodimericcytokine containing a p19 subunit and a p40 subunit, and were found toresist collagen-induced arthritis (CIA), a mouse model of rheumatoidarthritis (Table 5) (see, e.g., Holmdahl, et al. (2002) Ageing Res. Rev.1: 135-147; Luross and Williams (2001) Immunology 103:407-416; Durie, etal. (1994) Clin. Immunol. Immunopathol. 73:11-18). In contrast, p35knockout mice, which are deficient in IL-12, a heterodimeric cytokinecontaining a p35 subunit and a p40 subunit, exhibited exacerbated CIA,in comparision to wild type controls (Table 5). The p35KO, p40KO, andp19KO mice were prepared from the C57BL/6 strain of mouse.

TABLE 5 Collagen-induced arthritis (CIA) in wild type, p19, p35, and p40knockout mice. Incidence Clincal Genotype (diseased/total) score Day ofonset (mean) C57BL/6 (control) 10/18 2.4 29.8 B6x129F2 (control)  8/172.4 27.3 p35 knockout 12/15 4.6 27.0 p40 knockout 0/9 0.0 NA p19knockout  0/20 0.0 NA NA means not applicable.

Many modifications and variations of this invention can be made withoutdeparting from its spirit and scope, as will be apparent to thoseskilled in the art. The specific embodiments described herein areoffered by way of example only, and the invention is to be limited bythe terms of the appended claims, along with the full scope ofequivalents to which such claims are entitled; and the invention is notto be limited by the specific embodiments that have been presentedherein by way of example.

1. A method of treating a human subject experiencing a physiologicaldisorder comprising administering an effective amount of an agonist orantagonist of DCRS5 (SEQ ID NOs: 1 or 2) or of p19 (SEQ ID NOs:5 or 6),wherein the disorder comprises: a) rheumatoid arthritis; b) asthma orallergy; c) chronic obstructive pulmonary disorder (COPD); d) aninterstitial lung disorder; e) an inflammatory bowel disorder (IBD); orf) an inflammatory skin disorder.
 2. The method of claim 1, wherein theskin disorder is: a) psoriasis; or b) atopic dermatitis.
 3. The methodof claim 1, wherein the IBD is: a) Crohn's disease; or b) ulcerativecolitis.
 4. The method of claim 1, wherein the interstitial lungdisorder is: a) idiopathic pulmonary fibrosis; b) eosinophilicgranuloma; or c) hypersensitivity pneumonitis.
 5. The method of claim 1,wherein the antagonist comprises a binding composition derived from theantigen binding site of an antibody that specifically binds to: a) DCRS5(SEQ ID NO:2); or b) p19 (SEQ ID NO:6).
 6. The method of claim 5,wherein the binding composition comprises: a) a polyclonal antibody; b)a monoclonal antibody; c) a humanized antibody; or d) an Fab, Fv, orF(ab′)₂ fragment.
 7. The method of claim 1, wherein the agonistcomprises: a) DCRS5 (SEQ ID NO:2); or b) p19 (SEQ ID NO:6).
 8. Themethod of claim 1, wherein the agonist or antagonist comprises a nucleicacid.
 9. The method of claim 8, wherein the antagonist comprises: a) anantisense nucleic acid; or b) an RNA interference nucleic acid.
 10. Amethod of diagnosing a physiological disorder comprising contacting abinding composition that specifically binds to DCRS5 (SEQ ID NOs: 1 or2), or to p19 (SEQ ID NOs: 5 or 6), to a sample derived from a testsubject experiencing: a) rheumatoid arthritis; b) asthma or allergy; c)chronic obstructive pulmonary disorder (COPD); d) an interstitial lungdisorder; e) inflammatory bowel disorder (IBD); or f) an inflammatoryskin disorder.
 11. The method of claim 10, further comprising: a)contacting the binding composition to a sample derived from a controlsubject or control sample; and b) comparing the binding found with thetest subject with the binding found with the control subject or controlsample.
 12. The method of claim 10, wherein the binding compositioncomprises: a) a polyclonal antibody; b) a monoclonal antibody; c) ahumanized antibody; d) an Fab, Fv, or F(ab′)₂ fragment; e) a nucleicacid; or f) a detectable label.
 13. The method of claim 12, wherein thenucleic acid comprises: a) a probe or primer; or b) a molecular beacon.14. The method of claim 10, wherein the sample is derived from a humancell, tissue, or biological fluid.
 15. The method of claim 10, whereinthe skin disorder is: a) psoriasis; or b) atopic dermatitis.
 16. Themethod of claim 10, wherein the IBD is: a) Crohn's disease; or b)ulcerative colitis.
 17. The method of claim 10, wherein the interstitiallung disorder is: a) idiopathic pulmonary fibrosis; b) eosinophilicgranuloma; or c) hypersensitivity pneumonitis.